If you have and know how to use ordinary shop tools, there's no good reason you couldn't fabricate your own print washer (or slot processor, which I've very much considered) from sheet acrylic that's readily available, either from home improvement stores or specialty plastics dealers.
The hard part might be getting the correct solvent weld adhesive -- methylene chloride is the best for this, but it's hard to get even in the USA. I have a tiny bottle, somewhere, that I bought when I was fabricating something out of plastic (I've forgotten what, now, it's been fifteen years or so). The liquid cement for plastic models, that comes in a bottle like nail polish with a small brush inside, is the stuff, but it was quite hard to find last time I wanted some. It's possible plumbing cement (the kind for both PVC and ABS, which has a broad spectrum solvent mix) could work, but it's messy to apply with the swab in the can, thickened (with the wrong plastics), and usually colored (so you can see when you've gotten coverage, so your pipe joints won't leak). Acetone, readily available at Big Box and hardware stores, doesn't work as well, and the other solvents they have (lacquer thinner, if they still offer it) are worse. Enamel reducer is only found at paint stores that sell automotive paint, these days, and isn't really any better. Then you're down to trying to find a source for xylene/toluene (separately or in some mixture), which still aren't really the best solvents for welding acrylic.
Alternative could be to use clear silicone (the kind that's the same as aquarium sealant, but 1/3 the cost due to not being marked for aquarium use), but then there are cleanup issues and the difficulties of assembling and clamping with an adhesive that has very high viscosity and some level of tack, but won't really hold until after considerable curing time.
Still, if I had a table saw, I might well give this a try. Acrylic sheet isn't expensive, compared to buying a slot processor or print washer...