I got the set from Tirerack.com. They have about 4.5" of backspacing. I have watched that wheel for a while, cuz I'm cheap
... and almost got the 18" for $112 (which is a good price too) because they were sold out of the 17" rim. Last week I just happened to look online and they had some 17's in stock for $72
I couldn't pass them up! I see now that they only have the 18's listed again. One might put a phone call in to check to see if they had anymore 17's somewhere if they were interested.