I haven't looked hard as I like the 5.10 shoes. They are too narrow for my right foot post surgery though.

Amazon has shoe stretchers for cheap that will stretch the width to your like. Get your shoes wet, put the stretcher in to your liking, and let it dry while under tension. Do that a few times and you'll be fine.

That'll probably get you to 2E or maybe even 4E. If you've got giant flippers, I don't know.