this is the closest i could find on PAF having MiG-29s. the article just hints it.
PIR ARMS CONTROL LETTERS
LETTER OF SEPTEMBER 1999
In the last few years there have emerged new trends in the area of arms export from Russia and, in particular, re-export of some Russian-made arms and military equipment through other states (mostly FSU) to the Middle East, South Asia and East Asia.
To start with, the Pakistani authorities continue their persistent efforts to establish military-technical cooperation with the CIS states, above all, with Russia and Ukraine. The relationship inside this triangle is far from being ideal but there are all conditions for their harmonization.
When official sources announced in 1996 the signature of a contract between Ukraine and Pakistan on the shipment of 320 tanks, the Russian mass media primarily condemned this deal as a Ukrainian attempt to take a Russian piece of pie. In Russia, this deal was called treacherous. Moscow resented that although 80% of the T-80UD tanks assemblies were made in Russia, Kiev allegedly refused to share the profits. Russia even tried to hamper the deal; the Government denied the Malyshev plant (Ukraine) supplies for artillery systems and electronics. However, these attempts failed.
Thus, the Ukrainian-Pakistani deal has become an apple of discord for Russia and Ukraine, although in different circumstances it might have been an example of subtle export policy of the two states.
Russia still adheres to a political decision that it won't sell weapons to Pakistan in order to not damage its relations with India – Russia’s strategic partner in the region. If it hadn't been Kiev, Pakistan would have acquired the tanks in France. Kiev actually played into Russia’s hands since $150 million out of the $650 million deal went to Russian enterprises under inter-firm cooperation agreements.
Moreover, besides hard currency benefits in payments for Russian spare parts and assemblies for the Ukrainian tanks, Russia got another big bonus - to maintain balance in tanks India had to urgently purchase more advanced models. Upon arrival in Pakistan, most of the Ukrainian tanks were deployed in regions near the Indian border. That's why the Indian military leadership intends to arm five tank regiments with Russian T-90S, making them the core of the Army corps situated in the plain regions of the India-Pakistan border, which passes through the Tar dessert. And now Moscow is ready to celebrate a new deal with India by shipping a large lot of T-90S tanks.
That's how the declared Russian-Ukrainian tank war turned out to be mutually beneficial for both parties. And Russian benefits are not limited to financial means, for Russia has a greater opportunity to influence the situation in the region.
Another problem for Pakistan is the necessity to acquire new fourth generation aircraft. It could be the Russian MIG-29 or Su-27, or some French or Chinese aircraft. However, the French aircraft are too expensive, and Chinese planes are of low quality.
http://www.pircenter.org/board/article.php3?artid=103
Hypothetically, we may presume that Pakistan will suddenly purchase the aircraft from Ukraine or Byelorussia. It is known that although aircraft production is situated in Russia, both states possess the SU-27 (Ukraine - 66; Byelorussia - 26) and the MIG-29 (144 and 82 respectively). Former Soviet republics enjoy the right to sell some outdated military equipment and to purchase modern models (naturally, in Russia at a good price on the basis of good-neighbor relations and mutual respect). These conditions may encourage even Kazakhstan to arm Pakistan. It is likely that some of the aircraft will not be second-hand but brand new. It will be difficult, nonetheless, to verify the truth.
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for the rest of the article click on link. anyway the article also talks about tanks so lets carry on talking about tanks and the general ukrainian equipment given to PK.