Check out TAP Plastics. There are a couple locations in San Jose. Tap Plastics provides cut to order acrylic, Lexan and other plastics and at least at the store here in Lynnwood, WA, they have a scrap bin that they sell by the pound. For $3-$5 you can get more than enough to do all the plastics. My recommendation would be 1/8" Lexan (Polycarbonate). I make my own protectors as well as new plastics with water slide decals (Only make them for myself, sorry). The plastics can be rough cut with a band saw, scroll saw a Dremel or even a hack saw, then finished on either belt sander or with a Dremel with sanding drums. If you sand the edges with finer and finer sandpaper you can ultimately polish them to be perfectly clear.