Yes, many people did this before! But the ones already out in the wild didn't fit well on the bobbins of my Pfaff sewing maschine. Instead of searching, I did a fast version of my own. 

In this way, this a a remix without a parent modell. 

I printed them in PETg and they work great for me.

The FCstd-file is for FreeCAD - great open source solution for 3d cad.