I found this sign affixed to a courtyard fence on Washington Street and West 10th in the Village, a mile north of where it was found originally in what was named Tribeca long after the sign was removed from that location. In the 1960s, most of the area was torn down for the new World Trade Center complex. Oddly enough a short piece of Washington Street was allowed to remain between Vesey and Barclay Streets as a pedestrian path, so the intersection still exists, though it’d be unrecognizable to people who were around when the sign hung there.
Navy blue and white signs like this first appeared on Manhattan street corners in 1913. They were also used in the Bronx, since until 1914, Manhattan and the Bronx were the same county (New York County). I have one such sign in my possession, purchasing it from a flea market on 6th Avenue and West 28th (the location remains an empty lot!) in 1988 for $50. I’m told these signs run in the hundreds these days.
Unfortunately it seems that the property owner has altered the sign (see Comments)