score:2
Buy it online, and have it sent to your hotel. Contact the hotel ahead of time, to let them know to expect the package(s). Some hotels will charge a nominal handling fee for packages. Most, in my experience, don't.
Online orders in the US for commodity items are almost always cheaper online than in brick-and-mortar stores for obvious reasons: Less overhead.
When I'm in the US I almost always "stock up" on things... I have electronics, clothing items (those of which I'm certain of the correct size), or recently an engagement ring, all mailed to my hotel.