I understand your frustration, even the "extra wide opening" pairs of boots are to small fro my calves. There is a shoe company out of England that makes custom boots, they have a variety of styles and heel hights. The website is
http://www.divine.co.uk. This company was the inspiration for the movie
Kinky Boots. I must admit that they do cost more than $100, probably running about $250 depending on exchange rate. I'm currently saving up my pennies to buy myself a pair. Probably the 2.5 inch cuban heel with removable upper strap in leather.
FYI: they sell some "interesting" items and the site is probably not safe for work. As far as finding the boots, in the left column, click on made to measure. It gives all the details of their custom work and the styles you can do it with.