Don't commiserate about your broken zipper puller. Most  zipper pullers will break sooner or later.  But there is hope: This replacement puller is adaptable to the size of your readily available paper clip.

The enclosed .stl file will most probably not fit to your clip (there are just too many clip sizes). Don't give up but proceed as follows:

1. Download and install OpenSCAD from openscad.org.
2. Open the enclosed .scad source file in OpenSCAD (File/Open), fit the size parameters at the beginning of the file to the size of your paper clip and export the result as a .stl file (Desing/Render, then File/Export/Export .stl).
3. Print a prototype puller. Test it with your paper clip, adapt the parameters if necessary and print another puller until it matches your clip.
4. Install the clip on your zipper.
5. Glue the two puller halves over the clip (I use Revell CONTACT Professional). Squeeze it with a fastener and wait for the glue to dry (severeal hours). Hot glue instead of Revell is an option for the impatient.
6. Zip.