Looking for a very quiet apt in Midtown

I'm looking for a ~$3k 1BR apartment in Murray Hill / Kips Bay / Gramercy that's very quiet. One of my pet peeves is hearing heavy footsteps from above or talking through shared walls, so internal sound insulation is pretty important, in addition to the usual quiet street and good windows. A little bit of research suggests that some prewar buildings may be the best bet, with thick plaster walls and heavy floors. Someone also mentioned that the lack of an external fire escape suggests that the building had fireproofing insulation between floors as well. Gut renovated buildings may remove the plaster, and that might be something else to watch out for. Anyone know of any such buildings? Open to some other areas in Midtown, too. Thanks!