[RogueEngineer]

Personally, I'm a fan of Eastwood's Rust Encapsulator products. I would buy a pint it for touch ups.

Grind out as much rust as you can, and dab the encapsulator on. Make sure you really mix it up as the resin tends to settle at the bottom. I've used it with good results so far. I even have it on some exterior facing components on my Land Cruiser and its help up well for a couple years now. On an interior I suspect it would last nearly indefinitely.