C-130s - acquiring used or new C-130s is not unrealistic given that we have used them for decades, and our fleet could do with some further investments in either upgrades and additional units.
Cobras - The US was always willing to sell these as long as it didn't have to subsidise them. If they've been released, either the Pak government/army have had to swallow their pride and stump up the cash, or the US is willing to make a one-time waiver, given that the US probably just wants to get rid of them.
Vipers - Same as above for the Cobras. In addition, the PAF were ALWAYS going to buy EDA units and possibly upgrade these to V standard. The same approach which has been used with the Mirages (scooping up all available units from around the world) will be used to augment the Viper fleet. AESA equipped Vipers are a relatively easy way to provide a counter to the Rafale. New Block-70/72s are unlikely as the US will probably not subsidise their sale and we won't have the cash for an outright purchase for any significant numbers. However, a few token examples can't be out of the question (8-12 units).
Su-35/J-15 - Extremely unlikely for several reasons. The most notable is that the Indians will find it relatively easy to develop tactics against these in PAF service because of their extensive experience with a similar type. The main reason why the Indians didn't go for the F-21/Block-70/72 was because of the PAF's decades worth of experience with the Viper - there's no way the Indians could generate expertise and tactics on the Viper which the PAF wouldn't already be aware of. The same applies if we were to acquire a Flanker derivative. In addition, the PAF isn't really seeking to acquire a completely new type, along with the required support and weapons structure needed. But the most obvious issue is that we all saw how the Flanker performed against the Viper/AMRAAM combo last year - why would the PAF want a lame duck? The PAF LOVES the Viper/AMRAAM combo, expect the same thing we've done with the Mirages for the Vipers, these will be with the PAF for decades to come.
Side note - if a number of people make wild and speculative claims, some of the claims will eventually be right. Doesn't mean everything they say is the gospel truth...most of it is probably BS and the usual rumour mill which goes on in military circles. Threads like these are a damning reflection of the country at large if people go ape shit over the possibility of a few Hercs and the Cobras which we were meant to get anyway.
