Oh, I would have been all over that for a project. But then again, I have a soft spot for these neglected orphans. Or is that a soft spot on my skull? Anyway, if it was mine, the first thing I'd do is tear it apart, blast the snot out of it with carb cleaner, and give it a soak in Evap O Rust for a few hours. It will strip off the bluing, remove/neutralize the rust, and leave the bare metal with a protective coating. I would then spend days sanding it out to 600 grit, then take a day off work to rust blue it. But I am, admittedly, a glutton for punishment, lol. My second option would be a satin Duracoat spray finish. Dress it up with some new grips (CZ will not fit) and it would be gtg.
Honestly, if you strip it down, I'd find it hard to believe that a bead blast and Ceracoat from someone local would be more than $150. Ceracoat used to provide contact info for certified applicators in your area if you called them. Don't know if they still do that or not.
I think you'll be surprised at what a sweet gun you'll end up with.