Wahoo!!! The Horizon Buy 1 Get 1 Free coupon has made a return!! You can find smaller 7.5 oz boxes priced at around $1.98 at Target. That makes them just $0.99 each when you use your coupon (a bit lower if you have a Target REDCard).
Keep in mind that prices can vary greatly, so you may or may not find this same price at your local store – but it is worth looking into!