DirtyPCBs has never done me wrong, and they offer a cheap laser acrylic service, hmmm!
Prices for 4-layer boards and boards larger than 100x100mm have fallen significantly over the last year (driven mostly by JLCPCB), which has hugely expanded the possibilities for hobbyist electronics.
Not affiliated either.
But if you need more than a one-off the savings are clear.
The SLA printing service is a real game changer too.
Been using 3D Print UK and have been thinking of using digits2widgets and eventually getting a Form 2 to SLA print in house.
Most of my 3D print experience before had been with the filament type machines, and the DirtyPCBs SLA service is a huge step up in quality, and lower hassle/cost as long as parts are fairly small like mine tend to be.