ATC Watcher, if it's allowed by PPRuNe, may I offer this link as an interesting insight, at least regarding the Iranian Air Force acquisitions.
https://nationalinterest.org/blog/bu...-flying-111786
Indeed, as pointed out by Dixi188, their C130s, B707s and B747s were purchased pre 1979. Quite a few (if not all) 747s were in fact ex TWA.