How to give weapon to Allies ( like Packie )

Hy.

I would like to know, how could i give a designated weapon to my Allies such as Packie or Derrick( exactly at the mission Three leaf cover)
For example i would like if Packie use a sniper rifle or something different. The question is, is there some way to do this with a script or a mod? I would Really appreciate the help, thank you guys.

The best would be if you write a PM me at tendermester123@gmail.com