Hey jim, I ran into the same problem with the spalling rockers. On my fresh rebello engine, I made the mistake of using the wrong kind of oil. Just some off the shelf high mileage semi synthetic (with extra zinc). On the first go around, my cam survived, but the rockers didn't. I replaced all 12 rockers with nissan ones, and ran joe gibbs hot rod motor oil with lucas zinc additive and I had no issues. So the next summer, I used Amsoil ZROD oil. Big mistake, this time the spalling occurred on my camshaft and some on my rockers. I ended up replacing both camshaft and rockers. I think with our engines, you might need some extra zinc especially if the engine has a bigger cam.
I know that this information is irrelevant now that you have re-grinds, the cheapest OEM rockers can be obtained from Kameari engine works from japan. Yup, japan! I got a set of 12 for $450 Canadian shipped to my door. Cheaper than local dealers and courtesy parts.