DIY board. I designed a no-stabs matrix-only PCB (the Pi Pico MCU has to serve as the "daughterboard"). It's FRL 1800 and is one of my personal favorites, though I've since replaced the black spacebars with a couple of BOW keys that reflect the hold-tap mapping I set up; I've also changed it from KMK to ZMK.

Anyway, PCB orders usually have a minimum order of 5 pieces, so I snapped the numpad off of one and laser-cut a case of sorts, really just plates and spacers, and got "half-height" switches. My laser can sort of half-assedly dye-sub cheap PBT blanks, so I did a Timex Sinclair design. Later, I added feet, a 3D printed replacement one-piece spacer with a sidewall, and a MagSafe ring so it could be the keyboard for a Chrometab I converted to Debian.