Seems like it's now, busy season for DR travel. I have been trying to book a flight for July 4th weekend and they have all been expensive. I think if I book Monday, I can get a flight for under $400 from NYC.
Aeromar still has some tickets left for early June, but travel has to end on June 14th. Prices were $164 last time I looked. That is for a round trip BUT from Miami, not NY.