It is because the Typhoon Tranche 1 is limited to air superiority that it
isn't a good option for the PAF. The value such a platform brings to table is at-par with the F-16 Block-52/MLU - the PAF would just prefer more F-16s, especially surplus Block-25/32s.
It is the Typhoon Tranche 3 which is of real value thanks to its deep-strike capabilities, e.g. compatibility with SOW and ALCM, CFTs, etc. However, each one of those cost Kuwait $321 million per unit inclusive of spare parts, weapons and training.
Besides coming up with the money, Pakistan would need to get Germany on board to back a sale (with regulatory approval and potentially credit). I don't think Italy and Spain would mind (plenty of grease built there over the years), but Germany and UK will be tricky.
In terms of money, here is an approximate layout of how costs would need to be managed:
The cumulative value of a deal for 24 planes would be $7.7 billion U.S. Let's say $1.2 billion is for air-to-air and air-to-surface weapons. Roughly half of the $6.5 bn would be the cost of the actual fighter at fly-away cost ($135 million per plane). A 10-year payment plan would mean spending $325 million a year. The PAF's operating budget would need another $325 million per year in place to actually fly the Typhoons. The $1.2bn weapons cost might not be as high if the AAMs and SOW/ALCM are bought from Turkey and Pakistan, respectively.
On their own the Typhoon Tranche 1 wouldn't be of any added value. But if you add the Typhoon Tranche 3 for deep-strike, then buying some Tranche 1s to serve as air cover and air-interdiction assets would be interesting. That said, the operating costs of such a fleet (e.g. Austria said it'd cost $13 m a year to fly each T1) would skyrocket beyond the PAF's capacity. The PAF would have to settle with the T3 OR T1, and seeing the T1's deficit in deep-strike, it'd be T3, which then triggers a spate of requirements in financing and access (esp. from Germany and the UK).
@Oscar