Yes. You may cancel an order at any stage, but you will be charged for any expenses incurred by my USA partners. This will be a minium of US$10 if the order has been placed and US$5 if before the order has been placed.
With some orders it may not be possible to return the item to the store if you cancel after the store has shipped (e.g. custom orders, final sales, etc). In these cases I will let you know what your options are which may include sale of the item(s) on eBay.