When I dont have the time or the inclination to make my own pizza bases I always use the Pizza da Piero ones that gravityGirl recommended. I can get them in the SuperValu in the Pavilions in Swords and Tesco, Millfield, Balbriggan, both in the cooler section where the cheese is stored
Aldi sell really good pre-made rolls of pizza dough, you just have to roll it out. You get 2 large pizzas from one packet which costs €1.70. Even if you don't have a pizza oven it's worth getting it to make calzone in a regular oven.