Lots of machine shops use this stuff:

https://goodson.com/products/lb-1-cast-iron-spray-paint

It's a quick drying flat finish paint that looks like cast iron and keeps reconditioned heads, blocks, and such from rusting in storage. You can paint over it with any good quality high temp engine enamel.
jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!