I just discovered the Bloody Banquet line of fake novelty Halloween gory food. Some of the items include "Gore May" crackers featuring severed human thumbs, worms, and a rat's head.
Here's a butcher's package of human brains. Just leave it laying around the kitchen visibly so after dinner, your guests freak out wondering what they've just eaten!
There are also severed arms and a bloody heart in the collection.