It is common for China to sell Pakistan weapons better than itself equips.
Pakistan's A-5C, F-7P, and F-7PG were more advanced than what PLA had at that time.
Not true. F-7PG is a great dogfight but no BVR. J-8II was the only BVR platform that time with PL-11. Never sold.
J-10B is granted to PAF becos PLAAF is going to be equipped with J-20. By the time, PAF received J-10B(2013??), I bet J-20 shall also enter service with PLAAF..
PLAAF will still give the best to itself.