Summary

This object was made in Tinkercad. Edit it online https://www.tinkercad.com/things/2hJsfMn72fu
This version certainly repaired my headphones. It could be made more aesthetic and replace the internal tiny screws that hold the steel headband with protusions that mate with the other part that holds the wireframe earpiece, eliminating the need for internal screws. I only had 15mm woodscrews on hand so smaller diameter straight thread screws would look better.