This tram is currently up for sale on eBay .. check out: http://cgi.ebay.com.au/Melbourne-Tram-Vic-Rail-1921_W0QQitemZ120087939430QQihZ002QQcategoryZ1268QQrdZ1QQcmdZViewItem
They list it under "Railroadiana" and don't give the entire history of the tram! Not even a number!
Doubt it's an ex-Sandringham tram - although it would have been a St. Kilda-Brighton Beach one
It was up for sale on eBay previously: Click Me
Note that the price has been revised downward from $18,000 to $6,000.
I believe it is VR49.
I noticed this auction and sent the seller a message a few days ago - it is indeed #49
He must be desperate to get rid of that thing, he's tried selling it a few times before.