PETERBOROUGH, Ont. — Avery Hayes scored at 2:40 of overtime to give the Peterborough Petes a 4-3 Ontario Hockey League victory Sunday night over the North Bay Battalion, sending the Eastern Conference Championship Series to a deciding seventh game. J.R. Avon, Chase Stillman and Samuel Mayer also scored for fourth-place Peterborough, while goaltender Michael Simpson made 26 saves. Josh Bloom, Anthony Romani and Matvey Petrov scored for second-place North Bay as goaltender Dom DiVincentiis, who faced a penalty shot attempt, provided 40 saves before a crowd of 3,836 at the Peterborough Memorial Centre. The teams meet at North Bay at…