After removing the rust and grime from old chrome coin door parts like coin slots, etc., is it generally advisable to give them a shot of a clear coat like a Krylon Acrylic Clear? If so, gloss or semi-gloss/satin?
If you want maintenance-free, I'd polish with brasso, then wipe with acetone to clean off any residue from the brasso, then shoot a gloss clear coat like you mentioned to seal it. Just make sure it's UV protected so it doesn't turn yellowish over the years.