Quality paint meant for wood stoves will not burn off an exhaust manifold, though there is a curing process involved. I do not think stove paint would do well on a caliper because it probably does not get hot enough, but, I never tried stove paint on a caliper, so, I do not know.
Farm implement paint is mean to be put over rusty and ill prepared surfaces where shine and quality is not the top priority. As others have noted, it tends to be harder then car paint. Rustoleum tends to do okay, but, it is a bit soft, but, thinned (think I used Xyltol?) it sprays nicely on 4x4s and trailers using a regular car spray gun. Forget about waxing it.
I personally like Durabak bed liner and I am doing my newest project in it, forest green.
I do think Durabak has high temperature paint if you wanted to check it out.