I bought a seat out of a Scout boat at a re-sale store for my tin skiff. It's made by Tempress. They're sold by most of the sports retailers. I haven't had it very long, but it's a really nice seat, with a strong plastic shell, and good foam-supported upholstery. Their website, tempress.com shows all sorts of seat designs and combos. Worth a look.
I'm an Eighth Day Adventist. On the Eighth Day, God went fishing!