If you're lucky, Oreilly's might have one of those filter sockets. I just ordered one from BavAuto when I ordered a filter. Bimmerworld has OEM front brake rotors (if yours are non-vented) for $20 each
http://store.bimmerworld.com/blowout...ors-p1076.aspx . Nobody can come close to that price, even aftermarket. I have them on my car now, good stuff.