There are no bearings or bushings for a mechanical rear brake caliper. Only things to replace would be the self adjuster, self adjuster spring and brake pads.
when i bought the bike last summer the brake was already shot.but with a lil wd40 i managed to get it working there was needle bearings in it but all fell out.it does work but likes to stick every now and then.its not hydrolic(i wish)but the other crap.lil buggers are not cheap imo the brake caliper
ill figure somthing out