+1 for Pug. Screen printing wholesalers. You can use silkscreen, but silk is delicate. Printing mesh is nylon, much more hardy.
I've made a few hash screens and shakers for making drysift.
The first couple were old picture frames covered in screen printing mesh and they worked well, but a lot of work to process.
Then I automated the processes using an old oven rotisserie and a bucket with square holes cut in the wall. Those holes covered in mesh. It worked OK, but there was no housing around the tumbler drum, so the hash dust just floated in the air, DOH. My housecleaner/wife was less than happy.
The next incarnation was housed in a steel box, no floating hash dust then. "Happy wife, happy life" (or so they reckon


)
The tumblers are great for getting the bulk crystals, then to refine I have a few shakers. My initial shakers were hand shakers. A cooking stock container with a screwtop lid. Cut a round hole in the lid, covering the hole with mesh, then shake the crystals thru the mesh. You can purchase different grades of mesh and make specific lids for each grade.
Again, I got pissed off with sitting there shaking and shaking and shaking, so I automated the process using an old air pump and a stainless steel tea strainer.
An issue with drysift is that it oxidises. To slow this process down I press the dust into blocks or as some people have called them 'Pucks'.
The 'Processing Unit' :
The end result.