I don't know which stores retail the pillows, but they're all over Ebay at the moment.
If you don't want to go the Ebay route, my best suggestion is to try the nearest mall. You might also try contacting the company that manufactures Peeps, perhaps they can tell you who they've licensed to make the pillows and that could give you a lead.
You can find the company at www.justborn.com; they have a 'Contact Us' link that might get you to someone with answers. Good luck!
