That is a pic of one of my bikes. Those were 18" fast trekker blems that I bought for 15$ a piece and already had the wheels for another project. They were fun to play on and didnt last long and I later switched them out for some razr2's back when they were still a decent price.
If you still have your oem wheels, I would look for something to fit them. 22's in the front and 22 or 20's in the rear. I really like the 22's in the front, my raptor is setup like that and really works great.