Well, if it's casual Italian food in Japan, I guess Saizeriya fits the bill.
Hopefully there's one near the Naval District.

The reactions of real Italians towards such (replica) food would be another matter.

meganeshounen said:

The reactions of real Italians towards such (replica) food would be another matter.

As my teacher once said to a barista when he went outside Naples for work:

"Nice coffee! But, please, let's stop calling it coffee."

Well, he once traveled with 12 litres of water from his home because "you need water from Naples to make true coffee".

He's... peculiar.