I have used easypoxy before and did not care for its durability much. It is a poly-enamel. I used Interthane 2 part polyurethane with great results and no primer. Awlgrip is similar by another company. They cost more, but you only want to do this once not every season. If you are determined to go the cheapest route and use an enamel, Rustoleum has a line of enamel marine paint out and the local Lowes here stocks it.

I would also suggest using the same color as the gelcoat. I used white on my white boat. If it scratches or chips it won't be very noticable.

Just my $.02 from my experiance.