I'm looking in the same area. So, far I've only found really expensive hotels with balconys (kimberly, gotham, bar54). I just typed into the internet jumping nyc suicide and those came up. They are all very expensive places so you'd need to have a credit card with enough of a limit to get charged there. You'd also have to fit in with the very rich people there so you go unnoticed.
I actually called the kimberly to ask them about getting a room, and they thought I was suspect. They told me they can't provide information on the floor level when you get a room for yourself.
Other than that there was a story of a 17 year old running to a rooftop of a really expensive hotel. He just walked in and ran up to the rooftop of the mandarian hotel. He wasn't a guest there.
Most jumping locations are heavily secured in NYC (the vessel for ex). Also all of the locations I named have had multiple previous suicides. So there is the danger that they will have more secure measures now.
Most people who are jumpers in NYC live in the buildings they're jumping from.
Other than that, there are bridges which I don't know if those are high enough.