I very much doubt you see a timeline like the OTL with a Iran a rump state if that and a stronger Iraq and Pakistan.
Most likely Iraq due to geographic distance (although Iraq's anti-British government was supported by the Axis so it is maybe unlikely).
If a Shiite Islamic revolution does occur however they would have claims all over Iraq, Kuwait (which is 40% Shia minimum) and Iran, USSR and would have tremendous support from both ironically Persian and perhaps Kurdish groups.
Iraq is the most likely center given Dawa party was created in the 50s and their should be hundreds of thousands of religious faithful, Persians, clergy ect fleeing Iran to Iraq and set up shop hoping to reclaim their homeland like the Palestinians.
So maybe the Soviet Afghan war spreads all over the central Asian Republics? You know with Persian Tajiks, Tat, Azeris ect all present.