While it might seem odd to use a kappa's bodyparts as a relic, it's been done by real Japanese shrines and temples. Of course, those kappa remains almost always turn out to be mummified monkeys and similar upon closer inspection.
I brought the stuff you asked for.the number of shrinecomers will go right up!What are you trying to do?If I dress this kappa arm up like a sacred goshintai,
Goshintai: an object in a Shinto shrine that houses a god.