Based on what I've read, I think I will be going with with UK 9E for the Islay then. I'm really excited about my first Crockett & Jones purchase. I would have loved to make it into a retailer that carried C&J and really make sure I got the perfect size, but living in Alaska make that impossible. I was actually wearing the wring size Alden Indy for a year before making it to Leather Soul in Hawaii on my honeymoon.
Thanks for the help!