If your game uses traits it is pretty easy to pick up Stealth as a class skill for classes which don't already have it. Being charismatic could mean a lot of different things.
I'd advise looking at the Swashbuckler or the Savage Technologist. I suppose that the toughest question would be how to reload your ranged weapon. Using Quick Draw to pull multiple pistols ala Blackbeard could be an expensive but effective solution. Double barreled pistols could make this a little easier. Of course revolvers would work well too if you can find them.
Picaroon Swashbuckler (ACG)
fights with blade and 1handed firearm, primary abilities are Dex and Cha which means stealthy and charismatic
It is probably hard because most races only have two hands, so if you're holding a sword in one it will be difficult to reload a ranged weapon held in the other. Oddly enough this would work fine using a sling with the right feats.