Hardware implementation of Free42/Plus42 other than DM42?

[rex4good]

I saw this keyboard the other day, which got me thinking...



And after playing with the keyboard layout manager for 5min, this is what I came up with that might work for Plus42 as an input device (borrowed some idea from the Voyage series for CHS / EEX / ENTER).



I guess the question now is whether there is a way to run Plus42 on a standalone / portable device together with this keyboard, and they may be then put into some 3-D printed case?