Over a year later, and I finally acted on this. I purchased two used, supposedly-OEM heater cores from LKQ Online (a salvage yard network). I'm having them shipped to my buddy's radiator shop out of state because I'll be back there for Thanksgiving. He'll leak test them and repair them, if necessary and if possible, so that I'll hopefully have at least one good spare from the two. I've never had my heater core out of my LJ, so I'm asking if someone can put up a picture of some feature (like the Pentastar logo or the part number in a known location) that will help us make sure that what he receives is actually an OEM heater core. Anyone?