I have, and they are legal as per the Pakistan Arms Ordnance 1965 and all subsequent amendments.
https://www.unodc.org/tldb/pdf/Pakistan_Arms_Ordinance_1965.pdf
Notice how their bores or calibers don't come under any of the prohibited groups, neither cannon nor are they above 46 inches.
Now, it just depends whether the security company licensed them or not.
It isn't exactly an AK74 - those are really expensive if you were to buy an original Russian made and that one is actually prohibited. These are replicas, locally made or chinese (most probably local).
I thought the same at first, but the mag feels too thick to be pistol caliber. I remember seeing a similar weapon in a gun shop, it looked similar to the one in the picture from far but up close it was just a typical 222, painted black and with rail attachments and a different stock. Turns out this modification is pretty common and the gun sells for a lot higher prices with all that - even though the attachments are usually very low-quality.
Yes, It could be any AK variant but most commonly they're 'triple2'. Also, the handguard looks different from the usual 7.62 (Type 56s etc). Or maybe its lower part is just covered by the guy's clothes. Either way, AK variant, most likely legal.