It's not something I've looked into, but I know some people obsess over keyboards. Do the old computers use the same controllers for their keyboards? I vaguely remember doing stuff on the Beeb to read when more than one key was pressed. Since then I've used the old DIN plug keyboards and PS/2 before it all went USB.
3D printers open more options if you can print your own keys. I need to look into Tinkercad as someone at work recommended it.
!BEER
Old keyboards don't use modern switches but always work on similar principles, at the end of the day it is just making or breaking a connection.
Tinkercad is lovely if you just want to bash something out, I use Onshape for more complex stuff usually. Main think tinker is missing is things like chamfers/bevels and a proper history (it just has undo), they even added sketches recently