Well, I don't know about adaptors, but Machine Seven Automotive in the UK makes disc conversions, discs and drums in a variety of patterns including 5x130 Porsche, 4x100 Golf, 5x100 Golf, 5x112 Audi as well as the normal 4x130 stud fitment. They are on-line at
www.machine7.co.uk. I have neither any experience nor know anyone with experience with them, but I see their ad in every issue of
VolksWorld.
-René