If it is a light rust, just use 0000 steel wool and oil, gently. If it is just a bit of surface rust, consider using (lightly applied and polished) Flitz with your finger and a cotton cloth to wipe off (only a small dab needed).

It's hard to say value wise without a photo.

These are sought after guns and that is a great balance with the 6".

With rust, I would say it is worth no more than $700....probably would sell around $625.....but what an exceptional woods gun or deer hunting gun!

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Rather be outdoors