LightInTheBox offers the Kigurumi Kids' Unicorn Pajamas / Costume in Purple for $9.99 with free shipping. That's $12 under the lowest price we could find for a similar item elsewhere. It's available in sizes 100cm to 140cm.

Note: This item ships from China and may take two to three weeks to arrive. Uncheck "Add Shipping Insurance to your order" during checkout to remove the 49-cent feet.