I broke one setting the lash (which i didn't think was possible)

does anybody know of a source for these? they look to be 7/16 fine thread with a 3/8" ball cup (female at the bottom of the adjuster for Ball end pushrods). I can't find them in the ARP catalog and Comps Tech support is impossible to get a hold of. I thought these would be an advantage over the stud type but I soon realized that if one of them breaks you have to take off the entire rocker shaft to replace it since the stud has a collar below the rocker.

Trying to get ready for Mopars at the Rock in a couple weeks, I didn't even think it was possible to shear one just tightening the lash with a wrench, I'm wondering if the metallurgy is bad?