Thank you, but I think I came up with a solution we can live with -- it turns out that the boss is about as picky as I am, meaning any blue within a certain range is fine with him. And I think I've figured out how to get it -- I sent a trio of test files to Costco's photo center for printing and they turned out the way I thought they would. The (intentionally) bad logo is still purple blue, the turquoise one is still turquoise, and the one I was betting would be blue is the right shade.