I recently found an old wristwatch with a broken wristband and I couldn't think of throwing the actually still working watch away because of that. So this is what I did:
Can you do it to?
Well of course:
All what you have to do is get an old watch (which technically works) tear it down and modify the FreeCAD files according to the dimensions of your clockwork, glass and sealing. Then print the file and put all things together (maybe use some glue for the glass and the watch-face).
If you want to, share your files as a remix or something similar together with the dimensions of your watch, so others just have to print your files if their watch matches your dimensions.
32.2-30-32
glassDiameter-clockworkDiameter-sealingDiameter
The author hasn't provided the model origin yet.