HEAT oven to 400°F.
MIX meat, stuffing mix, eggs, onions and water just until blended. Shape into 32 meatballs, each about 1 inch in diameter. Place in 2 foil-lined 13x9-inch pans sprayed with cooking spray.
BAKE 20 min. or until done (160ºF).
MIX gravy and sour cream in large saucepan. Add meatballs; stir to evenly coat. Cook on low heat 5 min. or until sauce is heated through, stirring occasionally.