RealOEM.com * BMW E53 X5 3.0d Sport st.whl.airbag-smart /Multifunction

I'd say you need part #5, BMW 32 30 6 766 855, which is what connects your air bag to the slip ring.

The BMW connector alone might be available, you need to determine the part number prefix to have the full part number, i.e 61 31 8 379 424, but it might not be serviced.