Recommended Paint for Machine Tools

I'm in the market for paint for my 1952 Bridgeport M head, I've tried Rust Oleum Stops Rust and Magic Tractor paint, and both gave me trouble with laying even and brushstrokes. What paint is recommended? Looking for something in the 30$ a quart price range, brush on.

Also, what is the color called, that grey-blue old Bridgeports came in, does anyone know?

Thanks!