They can be easily rebuilt, can buy bits from Paddocks and other suppliers.
Dont know what a scrappy charges but just bought a brand new one for £43 + VAt and parts to rebuild the old one (brush set, regulator and rectifier plate) for about £12
Mines a 110 2.5 N/A these use a 45A unit probably same as 19J and many others, as the 65A unit was only fitted on later models and ones with aircon