Most of us don't have Italian water buffalo wandering about! Didn't see any in Italy either. I need to google them and see what they look like!
What works best is full fat unpasteurized, natural, milk. Cow would probably be closest in taste. But I bet goat would be interesting to try.
Yes, I had to google this and here is a great article about a guy who is trying to make the real thing in the US.
http://www.nytimes.com/2012/10/14/ma...anted=all&_r=0