The auction features three souvenir t-shirts from their trip to Coney Island. Each of the shirts, which are available in size small, medium and large, is signed by both Sirs.
While performing on Broadway, Stewart and McKellen shared photos of their various activities in New York using the Twitter hashtag #gogodididonyc.
Stewart and McKellen are currently starring in repertory productions of Harold Pinter's No Man's Land and Samuel Beckett's Waiting for Godot. The productions conclude their run at the Cort Theatre March 30.
All proceeds from the auction will benefit City Harvest, the food rescue organization that has been serving New York City for more than 30 years. City Harvest provides food to more than 500 community food programs throughout New York City and helps feed the nearly two million New Yorkers facing hunger each year.
Visit ebay.com/gogodididonyc to bid. The auction runs through April 3.
Visit twoplaysinrep.com for more information.