I hacked up an old telephone handset from my junk pile so I could have something vaguely ergonomic into which to mount the keys. Once I'd separated the front and back of the handset, I opened up tracks for the keys using a small cutting wheel on a Dremmel and also used it to drill a couple holes for a hand strap, then added epoxy in a few places to get the tolerances just right. I sanded the pieces and sprayed them black with a few clear layers of top coat. I ordered 7x Row 2, Size 1x1 Cherry MX Keycaps from WASD Keyboards and popped them onto the stems. I drilled holes near the tops of the three thumb keycaps lining up with the LEDs, and filled each with a dab of clear epoxy. A decorative ribbon was added for the hand strap, and a small block of foam was inserted on top of the circuit board to keep it in place.