The real question is will China sell Iran the J-10?
If Iran is willing to buy, China is willing to sell, although I would think the Iranians would be wiser to wait until the J-31/35 is ready and purchase that.
They maybe willing pay for all the bells and whistles so that their Air Force has a chance against the Arab nations across the gulf and any powers from further away. Considering their experience maintaining the Klimov engines on their MiG-29s, they have some knowledge to get the ball rolling if they go in that direction.
79 F-14s, 64 F-4s, 45 Mig-29s, 60 F-5s, 24 F-7s, and a number of their own domestic fighters round out the fleet that needs to be replaced; all told in the area of 300 planes; at 70 million each plus the costs to maintain and equip these planes, they will probably split the order between the J-31/35 and preferably the JF-17 (due to the common engine and lower cost) and if not that, then the J-10. IMHO, 200 J-31/35 and 200 JF-17 will allow them to have enough fighters ready to deal with a much larger force if they spend heavily on pilot training, and later in the other elements, EW and an integrated Air Defense network of modern radars and SAMs.
On the other hand, they may go for the J-10 over the JF-17 for the range and performance advantage though.
Pakistan may not be willing to “sell” to Iran or even help maintain Iranian fighters for fear of alienating Arab and western nations, so China may pay Pakistan to just ship parts to China or just pay Pakistan royalty for every JF-17 made.