As it happens, I found myself needing a right side footpeg a few weeks back while on a weekend trip. The only dealer in the area did not have one, and the TT/S4 uses a larger pin size on the rider pegs than on the passenger pegs (so the passenger pegs cannot be used). On the newer bikes (Daytona 6xx), rider and passenger pegs are interchangeable, which would have saved me some headache.
So we went about trying to find a footpeg that would work, and eventually came across one (the package wasn't well marked so it wasn't clear at the time what bike it was intended for). Turns out this rider peg was used on a lot of T3 models and early T5's, and they are cheaper (I think your RS might even use this part).
I bought one and mounted it without the rubber and curb feeler and think it looks and works better than the stock setup. My '95 Sprint uses the same peg (with rubber), and T3 Daytonas I believe used it without the rubber.
According to my invoice it's part #T2080901, and I paid $43.65.
[ This message was edited by: ezride on 2005-08-28 16:32 ]