Tom,
The rollers can be purchased from:
Colaw RV Parts
10389 Cimmaron Rd.
Carthage, MO 64836
877-548-2125
The video referenced by the Accuslide rep is here:
Looking back on my notes from Accuslide, the rep said the rollers are designed to be slightly higher than the wear bar. There is one YouTube video out there that has you cutting sections of the wear bar out to mount the rollers--not necessary.
I'm pretty happy with the way it turned out. We'll see how it does in the long run.