but I'm still a little skeptical on PAF getting PL-15 because it seems too big on JF-17 and there is hasn't been any records of PL-15 being offered for export that I know of.
Off topic:
In Soviet times, when Soviet VVS got it's new&shiny 4th gens, similar views led to a creation of two absolutely identical lines of missiles:
R-27 family for mig-29 and R-27E family for su-27, with latter being much heavier and more energetic, but otherwise exactly same.
Almost immediately it became obvious, what it is outright stupid: A2A configurations aren't that heavy to begin with(and difference in drag was negliable). So industry just created a difference for the sake of difference.
Now, back to the JF-17.
For external stores, PL-15 is just a better missile with more energy, lighter electronics(almost 100%) and (most probably) a newer, more modern seeker.
Even if you can't use it to its full aerodynamic range, which is not that useful for JF-17 to begin with.
It is more complicated for internal storage, but externally... if you can use PL-15 - use it.