Drive across the border to Pennsylvania. Much cheaper, much less hassle. No one in NY will know you have them.
Leave the phone at home or secure in an RF shielded enclosure while parked at the point of purchase. Use cash. Be aware some states such as California monitor out of state purchases of ammunition (trafficking residents.) These are intercepted once they return to their home state. Use a cutout?
Man PGR, don’t ya know a whole passel of Californians are heading to Nevada to buy ammo?