Very nice find.
Here's a similar tazza that I have with two jelly glasses. I think mine is late 18th Century, 1780-90 ish. Domed and folded foot, hollow stem, folded top rim and slightly wonky sitting top as you can see from the way the jelly glasses are sitting. Have read that on the 19th Century tazza's fairly early in the century they started turning the folded foot rim up instead of down and underneath. Not sure how true that is and whether all manufacturers followed the practice. I've only ever come across one anyway!
Cheers
Keith