Urethane sway bar bushings?

Anyone recognize the red sway bar bushings shown in this video? The video is about an engine rattle problem, but happens to show the rear bushings. They appear to say "5340" but I get nowhere searching with that (in combination with any number of descriptors). The vehicle is an "S", but the 50" uses the same ones. I’d sure like to own a set of these! Anyone know?