Hi Dave,
I know this is an old thread. If you're still around I'd love to take you up on the STL or model offer.
I found this thread while looking for 3D printable parts to repair a broken rod. I think your blank pieces could be useful for my project.
Then after that I could 3D print the whole rod and plastic weld the pieces together for proof of concept to see your design in person.
Please reach out if you're open to the idea.
I'm also curious if you've ever designed any 3d printable rod repair tools. Like a simple block to put blank on and rotate.