Seems a little (OK, a lot) high. Of course, if you are targeting black and want a newer Viper, you are restricted to '99 & '00. That will narrow your search. Look at the
Viper Classifieds on this site to get comparative pricing. For 2000, there are three black RT/10's listed (non-dealer): $55,000 (rarer cognac interior, 13,000 miles, CD changer, extended warranty); $56,500 (4,000 miles); and $57,500 (9,850 miles). The one you found seems pretty steep. Heck, you could fly out and see any of these three and ship it to your door and still save some big bucks. I would also suggest you call Bill Pemberton at (800) 889-1893 and see what he has. He is right up the pike from KC and usually has a good selection priced right.
Keep us posted, and let me know when you are ready to get a closer look at a Viper - the weather is awesome in KC!
Chris