Cost For Repairing Rust Damage

I have a small patch of what i believe is rust, it's sort of bubbly looking and i was wondering what price range it will cost for repair. It's about the size and length of a car handle.

It depends on if it is rust first or just bad paint with "orange peel", how bad the rust is, if it's rusted all the way through or can be sanded down, and location and size. If it's just bubbling and is rust then probably not totally rusted through yet so could possibly be sanded down to good bare metal then primed and painted to match shouldn't be too much as the sanding and priming could be done by yourself saving money and then have a painter paint to match and clear coat it.