This bug was fixed in Patch 1.84.171
The ‘Star of Paradise’ fountain from the Courtyard Oasis kit can’t be found in build mode. None of the filters work. The old place in build mode where the fountains used to be was removed and the new category water features doesn’t have it. Even turning on Debug mode doesn’t help.
I even tried to use Show All and set the filter to Sets. No fountain.
I also can’t copy it from an existing fountain with the eyedropper tool.
All of the water objects have a new category since Patch 1.77.131 called Water Features. It seems the fountain was missed when recategorizing everything.
There are two solutions you can try
Search for the fountain by name: Star of Paradise Fountain
Filter the pre-styled rooms by Kits and find the Piece of Paradise room. Select the fountain and place it on your lot from there.
There’s no solution for the not working eyedropper tool on this object.