May be able to reuse the rotor if it doesn’t have any damage to the surfaces. All the rebuilds I have watched (I’m rolling my eyes at myself at this point) they have actually put in new bearings in the rotor and use a special tool (I don’t know how to describe it other than like an espresso tamp but for a bearing). Have no idea about the other stuff though. I think as long as the e shaft isn’t bent or super scratched, I would use it, but I haven’t ever rebuilt a motor 😂