I've seen 4-5 Red R's listed for sale all over the country, even looked at a 99 R in Long Island. Honestly, even Ohlins aren't rare enough to be "the rarest" as there are a handful of sets floating around.
Oh and Yang has the OE CF interior
My first thought was the RTI Nav system, but that was Euro-only. Same with the 3 spoke "LeMans" steering wheel. How about the C70 subwoofer kit with 2 9" subs mounted in the rear seatbacks?