Speaking of custom shoes, I totally forgot about something I saw on the show "Shark Tank". There's a company called The Ave Venice that will do custom printed canvas shoes. They take a pair of plain Vans or Converse sneakers, put it in a machine, and it prints any image on the shoes. They don't offer ballet slippers, but it might be worth talking to them and seeing if they could work that in, if you could find a pair of plain slippers that would take the printing like canvas does. Worst case, the Vans slip-on shoes might be able to be gussied up after printing with a tartan image to make-do. Just a thought.