Someone is selling a spoon with what looks to be a similar mark and says theirs is probably made by John T. Dolan, c.1830. I can't find him in my limited reference books.
There was a John T Dolan who was born about 1777 in Ireland and in the hardware business in New York City by at least 1810. He died in 1862 and left a substantial estate to his family. I cannot make a firm connection between this man and the mark under consideration, but cutlery and silverware were sold by hardwaremen, so this gentleman at least qualifies as a possiblity.