power brake booster

I checked at NAPA about 2 yrs ago, and they said nothing was available as a stock replacement. You could try Rock Auto, but don't know if you will do any good. I would say, look in the Hemmings Motor News under "Services Offered" and see about a rebuilder like Booster Dewey, it will probably be pricey, will be done right, and should last your car a lifetime.