No need to restore them. All you need is cleaning rod with tips, patches, nitrile, vinyl, or latex gloves and can of G96 'Total Gun Treatment' spray. End of August is good time to start moving them out of your house. You can get a bit better price just before hunting season starts.
I just bought 1956 vintage 20ga Ithaca pump gun with 26" barrel. The gun is in virtualy unused condition. The biggest reason I bought it is #231120231 lightly entched on slide bar.
When I examined this gun in shop that # told me two things: the gun is pretty old

, and the original owner is already dead.

I'm goin' to continue hunting tradition by using this piece in sunflower fields to shoot doves.

Madam, you need to move on. Best Jagi