What about a Norinco NP-22? Chinese P226 clone with a rougher finish. Everything else I've heard about the gun is solid other than grips and cosmetics. I fear even this may be beyond your budget though..
Also, if you're concerned about rust, nothing a little gun oil before storage can't fix! I have a gun oil soaked rag on top of my gun safe and I always give everything a good wipe down before it goes back in the safe. With that and a small silica bead dehumidifier from crappy tire I have never had any issues with rust.