I'm sorry but I've no idea. I have looked on the National Archives but nothing is showing up.
It might be worth Googling Italian Baptisms. There are bound to be some sites which may point you in the right direction as to where to look. You could try looking for a Record Office/Archives in Turin and contacting them. I've never had to look overseas for an ancestor so I'm as much in the dark as you are. Sorry.
Emeltee