$50 is way too much to be paying wholesale for a plate, the sandwhich case has two plates and probably spacers and screws so you'd be buying a lot of stuff you don't want.
If you're thinking of buying lots (price breaks depend how may fit on a sheet so you'd need to ask what size they use) you could design your perfect plate on Swill's excellent website and get some quotes from local cutters to save shipping costs. That way you can get a test switch hole cut while you wait to ensure it's perfect before committing to a full order.
Since my project (and hopefully soon-to-be product) is currently a handmade affair, I would be looking at about 5 to 10 units each "round" on group order, so high-volume orders are not necessary at the moment, but I'm having difficulty finding anyone that manufactures something comparable for less. Lasergist for a standard 60% plate design is roughly $70 before shipping, and Ponoko doesn't get much cheaper either. Local cutters in my area are also out to make a fair fortune, it seems, as the lowest quote I've gotten using the same .dxf file from swillkb is practically $100 per unit!
I'd love to get the CouchSurfer up and running as an affordable case for people who have living room PC's or just want a lapdesk in general, but I don't want to overcharge people simply because I can't find cheaper alternatives.
If I go the Sentraq 60% case route, my cost is good enough to get the case down to roughly $170 "retail" after material and labor (as the wood portion is currently made by hand by me personally). I think that's a rather fair price, as Woodkeys.click and Datamancer charge similar rates for wood cases that aren't quite as specialty, and I put passionate handcrafting into each board. The quality of my woodworking is rather good, but I am no CNC machine, so the "perfection" aspect is something else to contend with when it comes to cost as well.
Thank you very much for the advice, _orange, and I look forward to contributing to this community even more!