Is this the right image?
RealOEM.com BMW E83N X3 3.0i CID control, MD
If so than ECS tunning would have it
Home Page > Search > 65126923321 - ECS Tuning Inc
If anything the part should be on the first site if i did pick the wrong one and than u can use the parts number in ECS tuning to find the part and order it aswell