There are vendors on eBay that specialize in this camera and have literally 100s of cameras in stock.
Early models are all-metal, while later ones incorporate some plastic, but are consequently lighter. At this age, I wouldn't worry about the reliability difference of the two, and simply plan to replace the body if it fails.
The Pentax K-mount has a lot of cheap, good glass. The 50/1.8 is standard and fabulous, the 28/2.8 and 135/4 are also amazing and can be had for under $50.
The camera is entirely manual, with no autofocus or autoexposure available. Optionally, you can put a button cell battery in it to power a simple exposure meter, visible as a needle indicator in the viewfinder.
I've been shooting these for 40 years, so I'm a bit biased, but I do recommend them just for their ubiquity and cheap replaceability.
I now recommend a Pentax MX, the same operation of a K1000 but better in every way. It was a more upscale all mechanical camera from Pentax. If you want a Canon, go for an Fb to Ftb for mechanical cameras or an A1 if you want more automated exposure options.
The best deals are probably the autofocus cameras from the 90s. With a little looking around you can probably find a Minolta XtSI with a 50mm lens for $50 or less. It is small and the lens, like all 50mm, is great. It also has a built in flash and a variety of of auto modes to simplify picture taking. Yes, they are cheap, plastic cameras that will not last a very long time. But you can get then for so cheap it doesn't really matter. The lenses tend to last longer. You can get similar deals on other brands too. Pentax autofocus cameras are super cheap but you can find Canon Rebels by the truckload as well as many Nikon (the N/F80 is my favorite plastic fantastic from them).
You don't even need a light meter really (though they are very helpful), basic rules like sunny-16 will go along way and will help teach you how to judge exposure.
1950-60s rangefinders can be a fun place to start. They've got everything you need, nothing you don't, are full mechanical, and often very cheap.
The most important thing is to get out, learn how film behaves and to learn how to take good photos. Don't get caught in the trap a lot of beginners do worrying about gear to the point they focus on that more than actually using it.
A Nikkormat FT3 or Nikon FM would also be good choices, but I like the compactness of the Olympus.
No it’s not! Pre-Ai Nikon lenses are also made out of toxic metal that will break modern cameras!
First is a FA, fully mechanical and a nice camera. Not sure about availability so.
The second, and already sporting stuff you also find on modern DSLRs, is a Nikon F4. At least over here more or less available, industructible (even half submerged in rain water pictures are great and the camera did not suffer).
Benefit of both is that they work with every F-mount lense Nikon ever made. Not sure about the latest G series without aperture rings, could be the F4 accepts those. And those lenses, if you get the good ones, all work great on Nikon's DSLRs up to the recent D780 and D850. And those lenses are available cheap used since everybody goes mirrorless. With a F4 and a decent set of lenses it is easy to go didgital on a budget, e.g. with a used good condition D700. Full format, feels a lot like a F4, both are professional bodies, and not too expensive.
Invest the difference to mirrorless into travelling to nice places where you can take nice pictures.
Oh, and using film helps improve your photography, if a picture takes time and money to develop you are much more concious about what you shoot.
Damn, now I'm motivated to break out the afore mentioned F4 again and some B+W film...
Edit: If you can get your hands on a Canon EOS1 your good too. It's Canon's F4 equivalant and Canon lenses are great. Canon does have less lens downward conpatability so. Nikon cameras are hefty, you feel what you handle, Canons are lighter and feel, well, not flimsy in comparison but you get the drift. I like hefty, solid cameras, others don't, so ouck your poison.
(Also easy to scan the negatives on a flat-bed scanner rather than having to make prints.)
TLR's can be had fairly inexpensively on eBay (as long as you're not insisting on getting a Hassleblad or a Rollieflex, for example).
Yashica's are still affordable and take excellent photos. Most models are purely mechanical — not even an exposure meter.
https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m...
A Nikon FM or FM2 for a fully mechanical camera with a light meter.
A Nikon F301 for an overlooked, very cheap but still really good camera.
The Canon A/AE-1 and Pentax K1000 get brought up a lot and are now surprisingly expensive for what they are, there are much better cameras out there for less but that don’t have their name brought up as much.
This is a huge rabbit hole to go down with how many cameras got made but if in doubt seek out someone in person and try to use one before you buy it!
[1]: https://cameraquest.com/voivcmet2.htm
As for camera suggestions, this is where it gets difficult and I know that I did not find the “right” camera for me right away. Initially I shot a digital SLR for about half a decade and while I got better as a photographer, I could never love the device itself and how it “made” me shoot. Got into film with a fairly small 50s Leica that I inherited, moved its 1949 Summitar 50mm lens over to a Bessa R2 after about a year because it has a built-in light metre, had fun with an original (fairly cheap as well!) Olympus XA, and these days I can afford Zeiss glass and a Zeiss Ikon ZM to match. But it sure was a journey and I feel I became a much better digital shooter thanks to it.
So, um… Recommendations? I like small cameras – preferably rangefinders – as they are easy to carry and forces me to work within the compromises they make in terms of flexibility for a given situation. If it was ten years ago, I would have recommended any of the Bessas (produced this millennia, built like tanks, and nearly purely mechanical) with a 50mm or 35mm cheap lens, but Cosina has either stopped or lowered production to a degree where you will struggle to find one at a reasonable price these days.
If you like wide angles (I do not really, as I struggle with anything below 40mm for unknown reasons) there are plenty of fairly cheap consumer and prosumer cameras from the 80s and onward with built-in light metres. My original Olympus XA was cheap and plastic-y as all hell, but oh boy was it small and could pack a punch with some good black and white film (straight from the scanner on good old Neopan 400 [2]). Sadly, if you want a 50mm on such a camera you need to go into the 60s and 70s, where the electronics easily become a bit more iffy. If you are willing to largely forego manual focus, there is also a whole range of cameras like the Fuji Klasse W, Yashica T5, etc. Just beware that some of these goes for crazy amounts of money these days and they are of course packed with electronics.
With all my rambling, I guess in conclusion what I am trying to say is that you perhaps should consider what you already know about yourself and your shooting preferences and go for what is affordable enough to be “a toy” to play around with to get your bearings towards “the right gear”. At least that is how I finally ended up loving the process of shooting both film and digital.
One potential advantage is the ability to use old Nikon lenses on newer digital cameras, but that's of limited utility when trying to use old manual focus lenses on modern bodies that aren't really designed for them.