This is a two part case for the 1upkeyboards Sweet 16 macropad/numpad.
You will need a Sweet16 pcb, pro micro, diodes, and switches to complete the keyboard which you may obtain from 1upkeyboards. You'll need to have the top portion printed before you assemble since it acts as the plate as well. Make sure to solder everything in the correct order, or you won't be able to get to the solder points for the pro micro if you solder the switches first.
For the case, you will also need 4 16mm m2.5 hex head bolts, and 4 5.6mm m2.5 heat set inserts. All of these are available from McMaster-Carr.