u/K-B-Jones

I have a number of old glass canisters. Some were originally peanut jars. They have a glass jar base and a glass stopper. The stopper has a plastic cap over the end which, when the stopper is inserted into the jar, forms an air tight seal. This plastic cap on a few of my cannisters have cracked with age. I'd like to replace this plastic cap, but i don't know what to call it when doing keyword searches online. Closest the search engines manage to come up with are ring gaskets, which aren't at all what I'm looking for. Can anyone help me? I feel like this should be a fairly common replacement part if only I knew its name. Thank you.