I got all my sprokets from Rocky Mountian ATV, they have all the sizes that you will ever need

 

I run 20x10x10 8 paddle haulers and boy do they hookup, I have been running 12psi in them to keep the wheels down! I would go with 7's or even 6's to get more wheel spin and less hookup. I have to start in 2nd gear standing over the bars to keep the wheels on the ground. It dunes nice with these paddles.

In races with Banshee's, my girl friend has a stock bike that I beat by 4 or 5 lenghts every time. She runs the same haulers I do and can only pull 3rd gear. One of the other guys I ride with has FMF pipes and pro-flow filter on his, running 300 main jets. He beats me by 5 or 6 lengths every time, he can pull 4th gear on the hill with his setup.

And to answer the $500 question, no the Big Gun pipe made no difference to these results. It adds way more low/mid to the bike, nothing on the top. That's why I'm going to try going back to the 13T and smaller jets.