When we were fitting out Southpaw (Brewer 43 steel gaff schooner) in Oregon
20 years ago, a local military Vehicle Club was fundraising by selling cases of military surplus paint. Aliphatic, chemical resistant, gawky camo green...$30 for 4 gallons. Couldn't abide the colour so experimented with black pigments (one caused the paint to rise up in a solid dome - weird), and wound up with a really nice dark matt green. Very tough paint. Repainted years later in NZ with LPU, but never liked it as well - most steel boat hulls aren't entirely fair, and gloss paint just accentuates the flaws.