I recently got a Basher Sabertooth on sale, but couldn't find any thngi's, so I made some ;)

BSR SABERTOOTH Wheelie Bar ( Hobbyking )

Wheelie Bar 60% infill, with supports
Wheels 90% infill, no supports (you can choose a small or big wheel)
Bus 90% infill, no supports

In the wheel(s) I use some common RC bearings: 5x11x4mm. You'll need two of them. It's a tight fit.

Enjoy ;)