You mention a few different phrases in your post:
"..way tricked out.."
"..everything new except the hull.."
"..1977 " (some call those Potter hulls)
"...way too much money.." at $22,500...
Barring any rotten transom or soft spots in the floor, this may not be the place for sympathy - there are people selling 20' foot boats for nearly that much which are even older.
If the old hull part bothers you, have a look at the following photos and figure how much you think this "old hull" might be worth:
http://www.classicseacraft.com/tomswhitewater.htm
Good luck/
mark