well really its flat track. this is what i would do and it wouldnt cost that much compaired to going with everything top of the line.
diamond j w/ shock conversion Aproxx $200.00
YFZ450 Shocks all around $ depends on what deal you can find, either that or some KFX fronts and like a ltz rear. thoes are cheap
G-Force Racing axle. i have seen them for as little as $190.00 shipped on ebay
CRJ Lowering kit. Check their site, or check ebay. they have front and rear
Tires. Maxxis Razors. Cheap and reliable
really if you do it right you could be looking at well under $800.00 for everything.