Tonneau cover help?

[Rwolfe]

What is the ring or what is it called that holds the lock into the cover? Looks to be some sort of ring but mine is not there an every time I unlock it an pull my key out the lock starts to come with it so the name of the ring or where to get a replacement would be greatly helpful

Thanks

 

[ncranchero]

The "43629" 1L5Z-9943629-AA is the retainer but this indicates it's only available with the lock assembly.