I used PPG's Concept Clearcoat on a sailboat dingy. Still looks the same after 3 years. Expensive and tempature sensitive, must choose the thinner by the tempature. I sprayed with a HVLP.

My color coats were also Concept DP primers.

Probably not do that again, too expensive and time consuming to learn and do right.
The clearcoats for Bows would probably work and be cheaper. I use one lately that is epoxy 2 part, the link has all the specs.