Converting Wooden Barrel into Cooler

Please excuse me if this does not seem to fit in this forum, as I was not sure but since it does regard carpentry I'm posting here anyways. I recently wanted to acquire a wooden barrel I saw for sale online. Figuring what I could do with it, I wanted to see the possibility of converting it into a cooler. Basically I'm not sure what materials/how to place an insulating piece about halfway down or so to be able to fill it with ice/ drinks. Is there a way to get a custom plastic piece to fit inside that'll fit? I'm also going to cut the lid and attach hinges to open/close it, and install some PVC piping that runs underneath the cooler storage and goes to a small valve to drain. Thanks for any ideas and help.