Window regulator roller and rivet

[FlameOut]

I was all set to re install the glass into my driver side door when I saw that I was missing one of those small plastic rollers that are attached to the arms on the regulator. Doing a quick search, I see that they sell them at LMC (30-0498) for $4.95 each but I have an old regulator with intact rollers from a 67 Chevelle I restored a few years back, and wondered if there is an easy way to pop off that roller from the pin (rivet?) and press it back into place on my 72 regulator arm? I was hoping to get this done today, and not have to pay $9 shipping for a $5 part at LMC

One of these