Some simple USB-A cover caps to replace lost ones. I included the FreeCAD model and the PrusaSlicer-Project.

You can use the FreeCAD model as a starting point for your own designs - I'm placing it in the public domain.

The 3mf file is the PrusaSlicer project  - it contains the “USB” label on the caps, which is not part of the STL or FreeCAD design.

You can print it with any material you like, simple PLA will be fine. No special support structures are needed if you print it with the opening towards the top.