I'm not sure if the heating elements are the same as non vaders but there was a post on BFC and the part numbers were there for just the elements. I think it was $70-ish US for one.
Crap, I don't think they are the same.
For non-sport, non-vader seats, the part numbers are 64-11-8-391-697 and 64-11-8-391-696. I forget which is the bottom cushion and which is for the back cushion.
Maybe Realoem has the part numbers.
I really should get back to work...
FOR VEHICLES WITH
BMW SPORTS SEAT
01 HEATER ELEMENT SEAT 2 64118391280+core
02 HEATER ELEMENT BACKREST 2 64118391281+core
Found this for you. I think it's for Vaders.