Everyone should know this information, just in case you find yourself needing a particular item from the parks! No reason to pay extra for an outside service to fetch a park item.
Call Disney Merchandise Guest Services and they will send someone into the parks to buy the item you want. You will pay for the item and the shipping. Here is the phone number:
They also have a website that has a ton of stuff – check it to see if your item is there. If it is not, just call them on the phone. Here is the website link: