Thanks Achipmonk, after studying the fit\misfit of the parts I found a solution. Since the new roller shaft was large than the regulator hole I drilled out the hole to 3/8 which gave me the dia fit and then since it only sat half way (1/16) thru the regulator I used my mig and tacked aound the back side. I thought about doing the sleeve route but finally decided I didn't want to spend the day running around chasing a more 'elegant' fix when I had a functional one at hand. Besides, now the next time it needs the be addressed it will be appearant what is what.
Since only repaired the faulty rollers (3) and bought 2 sets I'm thinking of stashing the other ones somewhere on the regulator for the next time. A hidden bonus of sorts...
