The G-Force hubs are good and extend up to 3" I think four around $110
If you want a cheaper option, the Suzuki LTR450 rear hubs will slide right on and gave you +.75" bot sides and you can order a set of 3/8ths axle spacers from durablue for a little extra. LTR hubs on ebay run around $40 and I'm not sure on the spacers.