Good question. They were sold by Ohio crankshaft.
I kind of think the rocker bodies aren't really any issue, nor the roller tips though some have tighter tolerances.. I'm thinking it's just the quality of that roller bearing. There's many part numbers for that same size under different manufacturers. The race is the problem or end to them.
I have a set of red ones I've not run yet that I picked up off of eBay a long time ago. I may try them out. I'm not really worried about losing needle bearings , for youre gpong to hear noise 1st way before.. and your side clearance at .010 isnt going to allow them to come out even if they could get by the races shoulder.. and that is not going to happen if you have the appropriate rocker shafts to run with needle bearing 'thick .250 wall induction hardened '