I'd go to Lonestar for a-arms. There are quite a few others, but I'm not sure how many of them make long travel for the banshee, but I'd most definitely go the extra mile for the longer travel if your desert racing. Houser is good, Quicksand is good, but they're more duning than racing, there's a bunch of mfg's. ARS/FX, JRD, the list keeps going.
I'd give TCS Racing a ring for your shock needs, www.tcsracing.com. He's pretty amazing with his shocks setup, plus his prices are a little more affordable over the big buys. But, you can't go wrong with Axis, Elka, TCS, Ohlins, they're all good, just be sure to get the valving right. Todd @ TCS is a master in the valving, just be specific with what you want.
Let us know what other questions you have.
Scott