What hardware is cost effective, but still has some longevity? I'd like to buy them hardware that will at least last 2-3 years. Please mention hardware needed for the entire track. I'm not currently up on the skills for CCNA in 2019.
You can get older equipment and newer equipment which is a good mix to teach students how to work with the old and the new.
For new hardware a few Catalyst 9300s should do with a few ISR 4000s and for the best of student at least two ASR 1001Xs and two ASA latest versions just be sure to order them to spec for what you have available. If you want a classic setup you can use 3x Cisco 2911s and 3x Catalyst 3750s with an ASA 5510. Insure all the products you get have the K9 Security Bundle so they can do crypto (SSH, SSL, IPSec, HTTPS, etc.) without that license everything will be unencrypted only (telnet, http, etc.). Normally you can get the older ones hardware licensed, ask the vendor to run the sh version command to verify the license before you order. You will also want to make sure you get things stackable if possible so students are not setting up LAGs when they can use stacking instead so they do not have to give up ports, though do teach them how to do this so they will know what to do if they are in that situation and are not able to do stacking or need to do both in a mixed environment.
You will also want to insure students know the different types of fiber, coax, etc. type connectors and how to set things up once providers have brought connectivity in through for them to finish the setup.
I got ccna 15 years ago, so can’t recommend particular models, but the core cert should still be about understanding L2 (switching) and L3 (routing) protocols. Pretty much any managed cisco devices should support more features than you need to know.
My CCNA was at least 15 years ago. I can’t remember exactly. I remember I did that and CEH at the same time.
Per my other comment, the subreddits I listed are by far way more informative than what you'll get from the HN audience. That's not meant to be a slam, it's just that the subreddits are a more targeted audience.