Never heard back from them so I gave them a call. Sounds like I'll be able to get just the one long custom stencil (as opposed to buying the whole kit).
Oddly enough, the lady said they only do quotes through email, and mine didn't go through, so she basically wrote and email for me and sent it in. She said someone would get back to me ASAP with a price. Ordered 24"x36", so it should cover the entire side of the hull and transom, with some overlap on the bottom, meaning I can curl the pattern underneath the boat for a seamless fade.
When I do get a quote, I'll have to ask them a question though. I want to make sure I'm just getting taller leaves of grass, and not thicker or skinnier. If they simply blow up the picture (or elongate it) , I don't think I'll be happy with the pattern.
I'll update when I hear back from them.