A while ago I looked at the 336 reps on ebay. The ones posted in the previous link look like they are a little off from the OEMs. They seem to have a more open fork. These ones look a little closer, but I don't know if I like their shadow paint job very much:
20" BMW X5 3.0, 4.4, 4.8 X6 STAGGERED WHEELS AND TIRES | eBay
Here are some side-by-sides: