I purchased the red cups at Walmart. They are marked as candy cups or ice cream cups and are manufactured by Wilton. You can probably get them at your local craft store, or use the link to a similar product on Amazon.
To make the Santa Belly, I used my cricut to cut the shapes using a free shape from Cricut- a square for the buck, and a long rectangle for the belt. If you don't have a cutting machine, it would be just as easy to do this by hand with scissors or a craft knife.
The exact dimensions were: ½ inch rectangle piece of black vinyl to wrap all the way around. Since cup sizes vary, just wrap it around and cut off excess. You have to angle it a bit so it doesn't bunch up. I used a 1 inch square for the belt buckle and removed a ½ inch square out of the middle.
Fill the candy cup with Hershey Kisses, or any candy, cookie, or goody you would like to include.
Wrap the cup up with the sandwich bag. No fancy stuff required. Simply place the cup into the bag. The two bottom corners stick out and look odd. Fold them into a triangle like shape and fold in to the bottom of the cup (similar to how a purse bottom is sewn). Use a piece of scotch tape to stick them to each other! Now cut the closure/ zipper part off evenly at the top. Bunch together, secure with twine and decorate with ribbon and tags.