A large development site east of City Hall Park is being marketed to buyers as a potential location for some future FiDi residential toweras if there aren't enough going up in the area already. Massey Knakal has the official listing for 1 Beekman Street, also known as 33-34 Park Row. If bought, the lot, which houses two low-rise buildings, would change hands for the first time in 40 years. To help with the visualization process, MK offers buyers two renderings by I.M. Pei's Pei Cobb Freed & Partners Architects of a glassy tower on the spot that makes use of the potential 87,300 buildable square feet. The Post first reported the opportunity yesterday, projecting that the site could sell for more than $50 million. Tribeca Citizen reports a rumor that veteran electronics store J&R is closing, citing "the value of Manhattan real estate vs. the state of brick-and-mortar retail" and portending even more change for this stretch. If the right developer takes the bait, could we have another (slightly smaller) New York by Gehry on our hands, and the beginning of a Park Row development boomlet?