Modern 3D printers allow us to print at tremendous quality and resolution. And some Chinese ones are quite cheap. My one of Texas Instruments TI-99/4A computers has a problem- due to a bad package and careless shipping it lost three keys. I still had keycaps, but it itself is damaged- the shaft is broken.
White ones are original, clear ones are new, 3D printed. It was quite hard to create a 3D model for this part as it is very small and has tons of details. But after four attempts I made it. On the left side of the image there are bad ones (the horse is also bad). Meanwhile on the right side there are some keys removed from the keyboard and disassembled.
Also, here is the STL file for this part. Take a note, that size of the key is ten times bigger (x10):
3D model in STL format for TI-99/4A keyboard key.
just scale the part to 10% and everything will be fine. Why? Because my 3D software is very buggy and only basic features are available. It is much easier to do bigger models in that software.