*glances around*
I'll let you in on a little secret I figured out this past year.
Get a polycarbonate roller from mcmaster with 1.125 ID. Put a bearing on one end, and put a versa hub on the other. You see, many common FRC bearings are 1.125 OD, and the versa hub's "hub" is 1.125. Super glue them in and you're done. You can either direct drive the versa hub (if you pick a 1/2 bore hub), leave it to run on the plastic with a 3/8 shaft, or bolt a 25 sprocket to the hub if you want to chain drive it.
That's it. Zero work rollers.
http://www.mcmaster.com/#8585k63/=zsp0kc
http://www.andymark.com/product-p/am-0209.htm
http://content.vexrobotics.com/vexpr...g-20141010.PDF
Not very expensive either, and clear so you can put all sorts of gimmicks inside them
