If the armature is good you can get the brushes from a good auto electric supplier like Faulkner (Romaine) Electric in Portland, Steve. If it's shot try Mohawk, Kirk's, or MCI. The cage can be hard to get off the shaft, as you probably know. You should put the cage in the blast cabinet and clean and paint it before assembly. Older MCI's used the same motor for the lavatory exhaust fan and the defrosters, pretty common motor but they are 24V.