Nah, it would be a new addon..
You'd need to make new animations (Standing holding two pistols, crouching with two pistols, and prone with two pistols, walking animation where you can shoot accuratly but are walking - with two pistols ect... Thats not all of them either)
You'd need to find a way of being able to fire out of multiple barrels (Take the Shilka, it only fires from one imaginary barrel in the center)
The optics for it wouldn't be that hard at all, though..
And if you make the anims for it all. I'm sure someone could make the model up in 10 mins (I've made 2 pistols before, but I scraped them after it looked rubbish, and I didn't want to make all the anims)
Gd luck tho
Basicly, no, it's not easily possible
- Ben