Yes, US Composites is a great source for epoxy, poly, fillers, and tools. I just recently ordered a two gallon kit of epoxy + some cabosil and microbubbles. Quality stuff, well packed, and a good price.
I havn't dealt with them as of yet, but I think they've got some good prices on foam, and I have heard others around here saying they are a decent company.
I've bought from them several times via phone and have no complaints. They have fast service, good prices and one of a very few online places that sell mat made for epoxy.
u s worked for me, did stingers, foam, deck, get the tooling resin it allows you to go back a couple hours later after the resin kicks to do additional layers, just don t wait longer than 24 hours on an overlay