There's a rebuilder in Nashville, TN. that specializes in all sorts of oddball stuff, including old GM starters, generators, regulators, etc. I found a set of brushes for the generator I used in my charging system tech tip article, for less than $5.00. (I've installed a bunch of them at a buck a set, but that was back when the labor rate was $7.50 an hour!) No website, but write or call if you've got a parts supply problem:

Todd's Auto Parts
206 N. 1st. Street
Nashville, TN. 37213

(615) 254-6264, (615) 256-1477

No, I'm not on the payroll, so I'm NOT advertising!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!