Wasted time and disappointment with Misdreavus...

Ok so I just spent a couple days leveling my Misdravus to lv 55 which is when it's supposed to learn Power Gem. Only to later find out it can only learn that move in the 4th gen games Platinum, HG, and SS. I only have Diamond. If anyone could EV train a Misdreavus in Sp. Atk. and Defense then trade it to me I would be willing to trade most any Pokemon in my PC.