It would appear to be in here. Some bracken and scrubby trees covering the site.
It could be now fallen and just not noticed but could very well still be there.
I am intrigued by strange bits of ancient history which pepper our urban landscapes. Sometimes they lie unnoticed by the locals, become climbing stones for kids or are simply overlooked. I recall about twenty years ago driving round a council estate in Northern Cumbernauld looking for a roman altar I'd read about (in the pre-Outerweb days!). Apparently the only roman altar still stood open to the elements in Scotland. I eventually found it across from a water tower. There were two kappa-clad youths with a pit bull on a chain drinking Buckie sat on it. I walked on...
http://farm5.staticflickr.com/4066/4547594611_53795a569a_b.jpg
They have put some railings around it now.