There's not much out there. Check out this thread and the links in it. The easiest and most available option is to cut off the stocker and get a slip on. Otherwise, watch ebay and be patient. They do show up there from time to time.
Oh...
Rob, I've been meaning to ask you about your high mount on your bike. Did you bend a Yosh system, or use a canister/pipe meant for another model? Looks sweet. Also, I don't think I had seen your bike with the black rims. Do you have larger pictures posted somewhere? I checked bikepics.com, but didn't see any newer shots there.
John