Oliver Stone didn’t want starving actors trying to pass themselves off as wealthy Upper East Siders in “Wall Street 2,” so he hired some of his uptown friends as extras. Stone’s been filming all over town with Shia LaBeouf and Josh Brolin. On Wednesday, Stone shot a scene in the East 65th Street townhouse of socialite “Baby Jane” Holzer, where the daughter of Brolin’s rapacious character is playing a piano recital for charity. Guests included Julia (Mrs. David) Koch, Vogue’s Hamish Bowles, Vanity Fair’s Amy Fine Collins, former Paine Webber Chairman Donald Marron, and publicist Peggy Siegal, as the wife of square-jawed war hero Chuck Pfeifer, who was in the original “Wall Street.” When the daughter finishes playing and makes a pitch for donations, Brolin barks, “What about you, Chuckie? You haven’t given anything in years.” Pfeifer replies, “Easy, Trigger! I just got out of jail.”