I actually pulled mine off today because I thought it was cracked. Luckily it isn't, it just needs paint. The part number is on the bottom corner. I don't think its on REALOEM. Good luck finding a new one, they aren't available from BMW any more. I think I saw them on here somewhere in the Schmiedman section.
http://www.abrahamsmotorsport.com/
I found it on the ETK part # 51 11 2 231 661.