I have never heard of EMRON but DuPont Imron is probably the most commonly available 2 part polyurethane http://www.performancecoatings.dupont.com/bowstreet5/webengine/dpc/common/Controller

It has been reformulated several times over the years and has lost favor with the custom painters who prefer clear coat paint systems. However for tough finishes I have not found anything that beats it.

Check local auto paint supply. For best prices call around and consider using a generic reducer.

The health concerns about using this product are real. The minimum requirements are free air flow and a proper mask and filter. If you are painting in a booth you need a positive pressure system.

You can use Interlux brushing thinner if you plan to brush or roll. You can get a pretty good finish if you roll and tip and then 1200 grit sand and compound.

My experience on repainting 20 - 30 year old catamarans is it's probably not worth spending more than 200 - 300 on repainting. These hulls are way past their design life. They may go for years or they may break in half next time out.