There are many sources of laminating epoxy. The www lists most, but the problem is you have to know what to get

I've personal experience with ACP, CST Sales, Aircraft Spruce, John Greer (aeromarine epoxy). There are many others. Quantities are typically quarts.

The very best epoxy (also one of the most expensive) is Pro Set, by Gougeon Bros. I use their 70 minute pot life hardener for heavy duty stuff like landing gear and prop molding. Skin lamination is usually the lightest with this epoxy.....it's the thinnest I've found
West Systems also by Gougeon Bros is also excellent but the slowest hardener gives only about 40 minute pot life. 40 minutes will be enough time but you'll have to do things quickly
EZ Lam from ACP is very good product that gives adequate pot life for laminating skins to foam.
Aircraft Spruce has several epoxies inclusing West Systems.
Aeromarine epoxy from John Greer is a pretty good product, inexpensive, pot life around 50 minutes with terrific shelf life capability (hardener is not amine based). Very good as a skin laminating epoxy, except it takes a little longer to get full cure. With any of these epoxies, the wing panels should be left alone to cure 24 hours.

The key things to know about skinning foam, a good vacuuming of all surfaces before assembly will help the finished product stay laminated. One could use the foam husks and either weights, or a simple press to assemble panels. Two pieces of MDF coupled with long bolts around the perimeter. 6 bolts are plenty.

About 15 years ago, I used vacuum for the first time and it is by far the simplest and best method for applying even pressure over every square mm of skin. Best over solid foam, no honeycombing here. The epoxy sources above also have vacuum apparatus available. ACP's 30" wide bag and their sealing strips are very simple and effective way to a sealed bag. I do both panels at the same time in the same bag. Paper towels are the simplest and cheapest breather material. Anyone interested in this approach, contact me direct