Pizza in Naples near Port
I agree that an hour will be awfully short - the port area is large and Im not sure where your ship will be and now long it would take to get in. Even if you grabbed a cab, the time would be quite brief t to actually have a meal. However here is a list of very fine pizzerie in Naples http://www.lucianopignataro.it/a/le-40-migliori-pizzerie-di-napoli-selezionate-dalla-guida-per-iphone-e-ipad/34464/ - at least a couple of them would be fairly close. Also if you get onshore google maps indicates a fair number of pizza places on or near the big street that runs around the port, You might look into La Masardona, in the Mercato, for example http://www.lucianopignataro.it/a/napo...
I'm not sure you can make it, because the port of Napoli is a huge area comprising many different docks and getting from the long docks to the city streets requires walking across large parking lots. So without knowing exactly where the ship is docking, it is hard to give reliable advice.
But if you want to make a mad dash for it, this might be your best bet: Pizzeria del Popolo in the piazza Mercato
Although pizza is a fast food, and some hole-in-the-wall places like this zip it out in the blink of an eye, they can also have a lot of customers and you have to wait your turn. Ask your crew to spend a few moments in advance reading up online about what to expect in a pizzeria so they know how to order what they want. The word for "to go" is "asporto" if you are running out of time and need to take it with you in a box.