Sorry I haven’t been on this blog in so long!
The link I posted for the source never really let me know much about it and now that link is dead. I do know, however, that it was sculpted using a lifemold and I’m pretty sure it was by this guy: frankippolito.com
So, you can’t really buy it unless you hire someone to make one for you.
But maybe you’re very amibtious so, here’s his mold tutorial: http://www.tested.com/art/makers/459616-making-lifecast-norm-zoidberg-project/
And I like this one for kind of showing how the fountian pump works and can be placed: http://www.youtube.com/watch?v=Ev31ApzmEog
But for something a little less grandeous, something more like this might work too: http://www.halloweenhellmouth.com/Project_Skull_Fountain