Preheat oven to 500°F. Flour 2 large baking sheets. Unroll each pizza dough on work surface. Cut corners off dough, forming total of two 10-inch rounds. Cut each crosswise in half to make total of four 8×5-inch rectangles. Arrange on prepared sheets. Drizzle each round pizza with 1 tablespoon olive oil or each rectangular pizza with 1/2 tablespoon olive oil. Bake until crusts are brown, about 8 minutes. Using metal spatula, loosen crusts from baking sheets. Cut round pizzas in half. Transfer pizza crusts to plates. Top each with prosciutto, arugula, and Parmesan, dividing equally. Drizzle each with 1/2 tablespoon olive oil and serve immediately.