Replacement 120v breaker type

[riverofcode]

I am looking to swap out a single 120v breaker for a double circuit one but without taking the old one out I was wondering if anyone knows what brand/model replaces them? I have a 2008 Tourmaster T40c. I am not looking to overload the panel but rather I really don't like the workdesk outlets running off my inverter circuit. There are several double breakers in the panel already so I know they are available....hopefully at a local bigbox hardware store.

thanks