US Market BMW part supplier for the empty connector, male and female pins with wires.
https://www.bmwpartslink.com/oem-par...21-61130005197
https://www.bmwpartslink.com/oem-par...21-61130005198
Connector, empty, 3 Pin to heater switch
https://www.bmwpartslink.com/oem-par...tz-61136931929
Connector, empty, 12 pin to clockspring
https://www.bmwpartslink.com/oem-par...20-61136954518
These are out of stock in USA as of 11/2019. Best way to get them is find the sellers on eBay, car-part.com and tell them to cut the wires and the connector from the salvage for you. I got it done for $25 shipped, generously priced so I can get it sooner. Shipping from Germany runs $12 just for that part, plus $7.5 for the part.
Atlanta BMW dealer has the same parts but does not have $24+ anal enlarging shipping fee. Shipping is reasonable around $7+ for standard one week.
Also the forum sponsor has great prices.
https://www.getbmwparts.com/c-navigation-map-updates-18
https://parts.bmwofsouthatlanta.com/