www.vagparts.com can get rear handles, genuine from Audi in Germany.
£35 each though. I ordered one, cos despite haveing a whole spares car, the rear right door handle is knackered. My 80CL has failed the MoT on the rear right handle.
I did just buy the left rear from ebay for about £7 though, new old stock.
I might buy a couple of the front handles from Poland and see what they are like, it's worth a try.
Front part nos:
813837206C
813837205C
left and right door handles for the Audi 80CL
813839205B
813839206B
Steve