My advice (despite some mixed reviews on feedback) is Bill Oehlke. Either google his name, or go to
http://www3.islandte...m.com/~oehlkew/ and he should have an inventory list.
Cecropia are the largest, most impressive (imo) and easiest to rear. And they have one of the most impressive caterpillars in North America. The Lunas are also big, bright green, and elegant. A close 2nd, imo. I believe both can be released in your area.
Also, double-check that your trees are Sweetgum and not Sycamore - which has very decorative bark, and smaller, seedballs than the sweetgum (although, I think Cecropia will eat either).
I say get cocoons and see if you like them. Chances are really good if they're coming from the fridge, you can get them to eclose within a few days of each other, and mate, if that's what you want.