There's probably a way of making these switches for less, if you're willing to trade money for toil and strife. Wind up toys have a very long roll of "wind up spring". 3D print a jig to bend a short piece of that into shape. Use somewhat translucent filament to print the switch. Or use a diffuser/matte thingy from a LCD monitor. I don't know. It'll probably be more expensive in the end but you'll feel good that you did it.
I think you can buy premade LED grid arrays. I would take one of those and overlay one wire per row, one per column, in tension and suspended a few mm apart. You could use a translucent 3d-printed framework to stabilize the wires and have a flexible piece above each junction to act as a button. Not sure how to make it click...
Can you imagine the flack he'd take if it turns out he'd been moonlighting whilst the GitHub ship is sailing though cat 5 with both the mast and the ship whore on fire?
