In a large saucepan, heat the remaining 3 tablespoons of oil. Add the onions and cook over moderately low heat, stirring occasionally, until softened and golden, about 12 minutes. Add the cherries and their soaking liquid and the lemon juice and simmer over moderate heat for 10 minutes. Add the meatballs and any accumulated juices and simmer over low heat until they are slightly pink inside and the sauce has reduced slightly, 5 to 10 minutes. Season with salt and pepper, garnish with the parsley and serve with pita breads.