I ordered some parts from them a couple weeks ago to build my own custom laptop, and they're finally on their way and I'm super excited! The article is missing this, but you can order hinges, keyboard (with or without case), trackball/-pad and all these things individually from them, and use them for your own purposes.

It is just mind boggeling how much MNT encourages hacking with their stuff. They even went and made a dedicated logo you can put on things that are made to work with the reform ecosystem / derivatives: https://source.mnt.re/reform/reform/-/blob/master/symbol-for-derived-works/mnt-based-reform.svg

You can also search for the founder Lukas F. Hartmann and find a couple interviews out there.