This is what's available, and I'll be having strips cut tomorrow morning. The redwood is nice heartwood, and both have vertical grain. My only concerns are whether the redwood has enough strength where the first 3/8 in. lip strip will join the taller stripts, and then the whole thing with a tension curve with the skin sewn up to it.

Probably all very fine, but, with zero firsthand exposure to others' work to draw from, I'd like to be sure. Thanks!