how about contacting the local community college culinary arts department? maybe the students could do it with oversight of instructor and work at serving and passing out appetizers/pouring wine etc. maybe they can even arrange for tables/setup etc.
I don't have an answer for your exact requirements but I do know a very good one gal caterer in Rockland county. Her food is delicious, she works with what you want or has many suggestions. If you don't find anyone closer who will cook on site you might be able to get her to go across the bridge and prepare you a wonderful spread.