I've had a couple of good experiences with madss.com
They don't keep much in stock, but they don't take long to get it (atleast it didn't take long to get what I ordered). They are also on the east coast, so things get to me a little faster than some other places I've ordered from. They are cheaper than ordering from triumph or anywhere else I've found.
I just got the luggage rack for the quick release sissy bar for the R3T. I had it pretty fast and it only cost $118.99. Triumph wants $139.99. And they have free shiping (within reason) for anything over $40. They say to call about large items because they may not be able to ship them for free.