Amazon has 12-Pack of 14-Count Trident Sugar Free Gum (Pineapple Twist, 168-Count Total) for $6.32 when you check out via Subscribe & Save. Shipping is free.
Note, you may cancel your Subscribe & Save subscription any time after your order ships. Select the later date from the "First Delivery On" menu to get traditional S&S checkout instead of adding to your cart.