I've arrived at a solution. I reached out to Adam Buchwald of
Circle Strings. Adam has made me a couple of guitars from him in recent years and he offered to allow me to order an Ameritage case through him so I'd get the dealer discount. At $400 it doesn't come in a lot cheaper but it keeps a hundred in my pocket and the dulcimer will have a good home in a top notch case. I sent a tracing and they're going to cut the foam so it matches the contour of the teardrop shape. The Edsel Martin is as much a piece of folk art as it is an instrument and I want to keep it safe. I'd have gone with Cedar Creek if a better option didn't come along.