They sent out a code a couple weeks ago to old customers. BLITZ30. Worth a shot to try using it. They also have a $20 off coupon on their site currently.

Part number is BMW Bluetooth v1. FYI, my x is a 2004 4.8is with nav and dsp but the changer only had the 3 and 6 pin connectors, no coax cable connected. They checked with their techs and confirmed that I would/should not need the dsp box. Need to call them to order anyway, as the product isn't listed on their site, so easy to ask them if it will work for your application.