Repairing older winch?

I'm new to FS sailing (traded a Lightning for my Scot). The previous owner replaced the winch system with a traditional rope halyard and jib lifting system. Although this works fine, I'd like to convert it back to stock and use the winch. I have an older all aluminum winch, and upon closer inspection the plastic bushings/bearings are missing on the jib halyard winch. Based on the main halyard winch, it looks like these should be a black plastic like material. But it also appears that the winch would need to be completely disassembled to repair. It.

Has anyone repaired one of these winches?