Here's a large supplier of Gunstock blanks located near Strawberry Point, IA. It's not too far from Dubuque. Depending on where you are in Wisconsin, you might want to make the drive to select one.
They list Claro and Bastogne. I believe all European walnut is the same species, though. Grain and characteristics are dependent on the microclimate the specific tree grew up in. That's why Juglans Regia wood from nut producing trees in California doesn't usually have tight grain, the trees grew up too pampered.
http://johnsonwoodproducts.com/gunstock_blanksRegards
Ken
