Frost Free Spigot Plunger Repair Question

[Taterman]

I have a frost free spigot with a damaged plunger part that is causing water to leak out the drain hole when the spigot is shut off. It's the cylinder located inside the handle. Does anybody know what this part is called and if it can be replaced? Thanks.

https://ibb.co/bxnSQ6

 

[Reach4]

The whole gadget is a yard hydrant, and I think the broken part may be called an upper link or clevis. You need to identify the brand, and see what parts they have available. https://www.plumbingsupply.com/partsforyardhydrants.html