Sfogliatella like I had in Naples?
You won't find any sfogliatella like you ate in Naples. Sfogliatella is the Neopolitans' pastry of choice and is eaten at all hours of the day. The turnover is such that many places can serve them piping hot from the oven.
The two places to the right of the exit of the train station are superb and always hot and fresh. And there are other wonderful places closer to the center of town.
Another thing is that the Neopolitans make 2 or 3 varieties of Sfogliatella. While we tend to find only the flakey crust version here.
Basically you will not be able to replicate your Naples experience here. But an old Chowhound thread may give you some ideas on places you might try.
Most or all of the places mentioned are still around, so you can have fun giving them a try.