Combine ground beef, veal, and pork. Mix in cheese, salt, pepper, and parsley. Slice olives length-wise down one side (remove pimento if necessary). Stuff olives with meat mixture, pressing to close.
Heat 1/2 inch olive oil in large skillet over medium-high heat to 375°F. Dredge olives in flour, dip in egg, and roll in breadcrumbs. Cook olives, in batches, in hot oil, about 3-4 minutes per side; turning once, until coating is deep golden brown and meat stuffing is cooked through. Drain on paper towels.