Pete,
Eileen says she can subtract $3 for each additional Gun Gack book above the first one, if they're shipped in one package. You can either order through riflesandrecipes.com and add a note of that in the space to make requests. (Most people us it for how they want them signed. We autograph every one that's shipped, but can add special notes for gift-books, also free of charge.)
Or you can call her at 406-521-0273.
