SALEM – A man who was caught peddling OxyContin pills in Lynn two years ago received four to seven years in state prison.Geraldo Contreras, 30, of 23 Rosana St., Hyde Park, made his plea Wednesday in Salem Superior Court in a deal worked out between Assistant District Attorney Marsha H. Slingerland and defense lawyer Randi Potash.Contreras was allowed to plead guilty to a lesser charge of possession with the intent to distribute opium before Judge David A. Lowy.He was arrested Feb. 21, 2009 at around 3:30 p.m., for changing lanes and cutting off another vehicle on the Lynnway by State Trooper John Fallon following a motor vehicle stop.During an inventory search of the gray Honda, police found a plastic bag in the center console of the vehicle containing 180 OxyContin tablets.A second person, Rodolfo Santos, 28, of Haverhill, who was a passenger in the car was also arrested and charged.