Gun? No, thanks. I'd bring my bow. I'm learning how to reload that girl in a second, and I've got plenty of arrows, thanks.
Just to be on the safe side, Kira's bodysuit would come in handy... sorry, personal reference.
Okay, first question I'd like to ask is why would I rip a drug-dealer off, and why would I be buying drugs? Anyways, Probably a M1911 because that's my preferred weapon in CoD Black Ops 2.