These are replacement brackets for Komplement 20167 by Ikea, which do not seem to be available for purchase from the company.
Things to note:
The wall bracket is looser than the original, but includes the retaining clip, so it does stay in the socket. If you are using a full width closet rod, there shouldn't be any issue. If you have the L shaped rod (like I was repairing) it may require some further adjustment.
Some modifications were made to the originals:
The Blender model files are included, and have dimensions so you can better match your closet hardware if needed. The rod bracket could be easily converted back to a single piece should you prefer.
I printed these in PETG for extra strength, so they were modeled to allow for shrinkage, support removal, and the profile for my Neptune 4. (This and being new to the part design process is why the fit is looser.) Changes I have considered are making the wall socket deeper and adding crush ribs, either of which could make the fit more feel stable.
The author marked this model as their own original creation.