Based on the year, I'm guessing the Iranian variant would have had the Phoenix, since it was based off of the AIM-47. Although it would seem to me to be alot of work to make the A-12 into an interceptor. Unless they were looking at only carrying one or two missles in a modified version of the A-12's Q-bay.
The other interesting thing is the A-12 was the highest perfoming variant of the Blackbird Family, since it was a single seat aircraft with a smaller fuselage (lighter weight and less drag) and the same propulsion system. Don't forget, the A-12 was designed for M-4.0 @ 120000 ft. How close it got to that is still secret. But given that SR-71 pilots have said the SR-71s top speed was M=3.55 to 3.6, based on atmospheric conditions, I wouldn't be surprised if the A-12 made at least M=3.8.
Also, was the Iranian version to use the J58's, or would they have been re-engined with J75's like the the first A-12 flew with?