By 1975 the Cold War had settled into a relatively short-lived equilibrium.
Sounds ominous.
Nice update, a powerful non-Islamist and non-dictatorial Iran is certainly an interesting change from OTL.
One nitpick, though: you mentioned
but the Garand is semi-automatic. The 1903 Springfield it replaced was bolt-action though, and assuming US small arm development went in the same direction as OTL there would still probably be a lot of those left over in storage to be cleared out in the mid-1950s.M1 Garand bolt-action rifles
Keep up the good work!