My friend,
first, Iran has many %ig-29, Su-24 and other 4th generation aircrafts to protect itself, and I sincerely believe that the F-4 or 5 are intended more to carry recon or training missions. Not much more.
But Iran's defences are more shore and ground based against US aircrafts and navy, as a US land invasion is out of question.
If we want to replace all ageing aircrafts, it would take billions and most of all a good supplier. Russia and China aren't, so who can we adress? Pakistan? Ukraine? Europeans?


It's not a matter of choice for Iran...