You're never going to make the under 50oz weight limit nor are you going to squeek by with the magazine outside the pistol grip no matter how much you want to dream it. There's no way around tthose items, and combined they = felony no matter what state you haul it in from or try to register it as.
If its got a shield over the barrel, that's another slap in the head.
Preban is literally your only choice in NY.
SA bolt carrier (not group, just carrier w/gas key) 9.3oz, FA 9.6oz
Buffer (carbine) weight 3.0~6.4oz depending on your selection or mechanical need
There's 12.3~15.6oz by itself and haven't even got as far as receivers, receiver extension, buffer spring, fire control group, pivot and takedown pins, barrel, barrel nut, gas block, gas tube, bolt w/extractor, firing pin, charging handle and siights.
And that's being gracious by leaving out dust cover and forward assist and completely forgoing any muzzle device.
The keltec PLR16, which forgoes aspects of the conventional DI system comes in at 54.72oz right out of the box minimally equipped absolute base model.