I just bought a Westfalia hitch with the electrical kit from Transportsysteme24 in Germany.
I found them on eBay.de and they responded to my queries (in English).
I had to go their site and order off eBay (since the ebay site would not allow shipping to the US.
However their website did, but our credit cards won't do. Sooooo after much correspondence I found that I could get the order placed to be invoiced and then pay vis PayPal.
They have the hitc for the 2015 listed here:
http://www.transportsysteme24.de/index.php?cl=alist&cnid=1&cat=suche_nach_fahrzeugtyp
The prices are in Euros and this is the best exchange rate for a long time.
The complete price for my setup including shipping was E 391.30 which came out to $433.56. This was for the hitch, electrical 13 pin VW wiring kit and freight.
So far they have been a nice company to deal with. Of course I have not yet received the equipment since the sale was completed this morning.
This got the Westfalia hitch for a 2013 JSW and the VW kit for wiring which ties the system into the trailer for T-ESP and light out detection.
If you use Chrome you can right click and translate the page (more or less). You have to go back to the German to click on a link and have it work though.