Where to get marshmallow peeps in February?

I suppose you want to know why I’ll be looking for peeps next month. The newspaper that we get has a contest every year (around Easter, of course) for dioramas using peeps as people. I’m having a sleepover with a few of my friends, and I thought we could put together an entry and take a picture of it and send it in. They’re gonna be taking entries in February, anyway. So that’s the story. The one problem: where would we get the peeps so early?