I've got a classic German - Car problem here.

At some point in the 115,000 miles my USA specification C280 sport must have been driven substantially with the ABS pump inoperative.

Like Audi, VW etc - these cars have a fail-safe that biases brake balance to the rear in such situations - and thus it chewed up the rear rotors.

My right rear one is slightly out of round/warped (driver's rear is fine)

I'm seeking one or possibly two good condition rear brake rotors but affordability is key right now.

Anyone have a donor or cheap one? They don't weigh much and I'll cheerfully prepay for the part + snail mail. AZ Autohaus has them for $28 - but refuse to sell a single rotor.

HELP

 

You might have to buy the rotors from autohaus, or you could go to a wrecking yard and seek out a car similar to your C-class

 

It may be hard to find them sold separately on the web. However, E-bay has buyer protection for most cars and parts sold. I did a quick search and found the following listings at the E-bay link below:
http://motors.shop.ebay.com/Car-Truc..._qfkw=1&_rdc=1

Hope this helps

 

Try this guy on e-bay he went out of his way to help me when I ordered the wrong rotors.
"CBRAKES" He is listed as a top seller.