Hi, Oddly enough, I manufacture 3 piece alloy wheels in sizes up to 17" diameter, but 18" wouldn't be too much of a problem. I also own an '87 TSI. Currently I sell my wheels mainly for road racing use. Price per wheel up to 10 sets would be in the region of $450per wheel, as below this quantity it's not worth setting up the CNC machines. Over 10 sets the price would come down to around the $300 ea...