For AWO/ORF receivers, they made some of the Century Golani receivers as well. TennGalil over on the Uzitalk forums, and others, have posted extensively on checks that should be made to ensure integrity of that component and best place I've seen it discussed.
TennGalil/Hillbilly Firearms has built VZ58s for customers too, but is known to have a significant backlog of work -- but might be willing to inspect for you. Am sure there are other competent VZ-58 builders too who know how to inspect for receiver quality, but don't have that list offhand.