I'm not sure if it's hard enough to remove rust, but bronze wool (get it at a hardware store) is softer than steel, and might not be as aggressive on the finish.
There is a recent discussion ==>
here <== that may be helpful. I've not tried these techniques, but have used a very small tuft of bronze wool dry wrapped around a "Q-Tip". Lightly using this "tool", followed by preservative gun oil (see a discussion on this site's "General Information" page) got me where I needed to go.
Marc
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Igitur si vis pacem, para bellum -
- Therefore if you want peace, prepare for war.