I've looked around.
The kid sand-/waterclam is apparently flimsy, very small (not even a 7 yr old could sit in it) and doesn't look realistic in the slightest.
The one Finfolk had, however...man, that's awesome!
I wonder where they got it?!

Couldn't find anything similar, so I bought a very life-like, inflatable green snake as pool- or other prop.
Was really cheap too, guess snakes aren't poular