Apologies, I read your previous post as acrylic OR enamel, so interpreted it as 1k.
Have never come across acrylic enamel 2k paints here. Can probably get it if I searched for it, but everything here is either 1k acrylic or enamel, or 2k polyurethane (generally an acrylic based polyurethane, polyester polyurethane certainly isn't common). I prefer polyester 2k's myself, but they are special order and have an extremely short shelf life.
Polyurethanes cover everything from primers to top coats to clear coats. These are definitely the most commonly used coating for composites work, and would wager they are substantially tougher than acrylic enamels.