Our Adria caravan is closing in on its 10th year and start to show its age.
There is a cover ring around the door lock that prevents water and dirt to enter. This ring has become brittle and finally gave up.
So I made a new one in Fusion 360 and printed it on my cheap but nice Ender 3. It was loaded with some HobbyKing silver gray PLA so that was what I used.
To get it in place, just do as if you put a key on a keyring.