I was just at the Burton flagship store in south Burlington (80 industrial parkway) and to my surprise they have one of those laser foot modeling machines that some footwear stores will use to fit you for running shoes. I believe they also sell Superfeet insoles there, so if you need better arch support that might be an option.

IMO Burton makes the best stuff anyway, especially bindings, so might as well check it out and talk to the shop folks there, and try some stuff on. There is a reason every other binding company has straight up cloned their heel strap design, it’s the most comfortable.