We have an older lady here in town. She has a very small house on a dead end street.
A little redneck has a bedroom in the house set up as her shop and does nothing but rebuild old alternators.
Might be a good resource if you ever need.
Brushes are easy.
But if a diode or the stator needs replacing on a roundback, some solder work is needed. A guy with experience would be good.
Honestly, I don't recall the factory alternator on my parents '69 Belvidere ever being replaced. That car wasn't junked until around '87. And never had a problem with the one in my '75 valiant - had that car about 6 years. But I've been through a bunch of rebuilt ones. Coincidence, luck, IDK ? Makes me suspicious though!