20150903_111401

Here are the "bearings". They are simply 3/8" delrin rod, cut into 5" lengths. You need 20/wheel,(100"). 3/8" Delrin rod can be had for 95 cents a foot, & comes in 5' lengths. You would need 17', (to allow for cutting) for both wheels.
This would cost $16. FS sells sets of 40 for $32, again pretty reasonable, & they are already cut.