Stripped metal cabinets - rusting

I have been struggling with the following rusting problem. Any assistance or guidance would be greatly appreciated.

I have original 1955 metal kitchen cabinets in the house my wife and I just purchased. I stripped the paint and the original baked enamel (pink) to get to the bare metal. I used a 6" orbital sander with 26, then 60, 100, 220, 400, and finally 600 grit sandpaper to achieve the shiny finish. My problem now is rust. I sprayed on some Rust-Oleum clear enamel, but that left the metal stick, bumpy and completely destroyed the mirror-like finish I had worked so hard to get. I had to re-strip.

So I am hoping someone out there has a solution for rust proofing these metal cabinets that will not take away the high gloss finish. Folks at Zinsser suggested Quick 15 ⇩, but that product is not available in Virginia.

Any ideas?

Thanks!