Thanks to the wonders of
Google, I found a company that sells dance shoes in wide widths.
They're called
Tic-Tac-Toes. I don't have any shoes from them yet, but so far that they've shown that they'll happily send you a catalog and swatches of any of their leathers on request. They'll let you buy shoes, try them on, and send them back, so long as you try them on on a carpeted surface. Their prices are reasonable (many of their women's dance shoes seem to cost about $70), and for a mere $20 more, they'll make any shoe that has a leather-wrapped heel (some of the short heels are painted to match) in any one of the 39 leather colors they carry. You can't return custom shoes, but they'll happily send you a non-custom version first to try on. I also saw a note in the catalog that said "we can make shoes in your fabric," but I don't know the details of that.
They say for real comfort, to purchase the "chorus line" shoes, which were designed for (you guessed it) people who dance in chorus lines, and who were regularly complaining about achy feet at the end of the day.
Again, I don't have any of their shoes in hand yet, but so far I'm extremely impressed with their customer service, their willingness to answer questions, their willingness to send swatches and otherwise have reasonable policies, and their prices.