”The West Wing”’s chief of staff John Spencer is making an executive decision. The actor is selling his 2,000-square-foot house, hidden among the trees on a hillside in one of L.A.’s prominent canyons. The two-story nest has 9 rooms, including a large master suite with his-and-hers sitting areas. Built in 1962, the property sits on nearly a third of an acre and is fully landscaped with a pool. (Monty Iceman of Prudential John Aaroe has the listing.) According to property records, Spencer recently purchased a home in the neighboring canyon for just over $1 million. And he’s not the only ”West Wing”-er on the move: Spencer’s TV chief Martin Sheen has also recently put his Santa Monica home on the market.