LightInTheBox offers the Wireless Fidget Spinner Bluetooth Speaker in several colors (Dark Red pictured) for $6.49 with free shipping. That's the lowest price we could find by a buck. It features Bluetooth 4.0 and is compatible with iOS or Android devices.

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