My bike started out black, but I replaced all of the plastics and the wind screen which was painted black (badly too) with new, white OEM plastics. That was the biggest expense. In your case, the orange wheels would be expensive; however, lots of people look to swap colors.
I went with a white, orange, and black color scheme. I really like the blue and white XBs, but I wanted something different. Buell never produced a white and amber Buell, so I made my own. I wanted something that looked like it came from the factory. Again to be different, I went with EBR (Erik Buell Racing) decals to be a bit more exotic and because I'm rooting for Erik's new endeavors, racing team, and new company. Let's face it most people don't know what a Buell is let alone an EBR... You should see some of the faces of folks who try to figure out what the heck it is. Because you have a silver frame, it might look a little off, but if you search the web for white and amber buell, there's at least one other white and orange XB9 with a silver frame and it looks really good actually.
Yes, my seat is a Corbin and there are plenty of options for the billet levers. The right side scoop and heat shield is from the Ulysses comfort kit. It's not expensive. The decals are from EBR's website and the 1203 decals are from a link I found on this site in another thread about decals. Other than that, I'm running a 190 rear tire, Gripster frame and air box cover pads, OEM frame pucks, ASB fork and swing arm sliders, and some LED turn signals from the Web. My thread is entitled "Creamsicle Buell Build."
One of the great things about Buells is that you can swap colors with other owners or buy different ones for pretty cheap compared to other bikes. Heck, one side fairing from a Ducati costs almost as much as what I paid for the entire set of brand new factory plastics.
Good luck!