I just want to add a place where I shop, which I by no means am affiliated with, but it's a store (and great online store) based out of the UK called Duo Boots.
They do shoes, ankle boots and boots all up to size 12/13 or like 44 in some types. The extra plus is you can in some define the width of the shoe/boot and even more so the calf width so the boots actually stay nicely snug around your calf. Check em out, Duo Boots. They are not cheap but they do have some amazing sales on occasion.
Another one, also not cheap, is John Fluevog out of Canada that also have a good site though very special taste in shoes and boots. They typically carry up to size 11.
Finally I've found Toms size 11 in women's actually are fairly large and in men's I'm typically a 10.5-11 but fit the Toms boots size 11 perfectly. Toms are also much more affordable than the two previously mentioned brands.
Hope that helps some people.
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