Demountable camper group

I don't know if anyone here can help me. I am looking for a composite panel supplier in the US who can construct custom panels larger than what seems the standard 4' x 8' panel. I haven't had much luck. Fiberglass skins urethane foam core 50-75mm thick. Anyone??

thanks

Oh, and new here but been lurking around. This is a wonderful forum lots of great info. Cheers

Nobody springs to mind for me but you never know, we do have a few American members
so sit tight!

Maybe the appropriate question is - does anyone know of a forum that is almost as good as this one for the US region?