It turns out that you can buy duck hearts at Ottomanelli's Meat Market (285 Bleecker Street) in 5 pound bags for something like $3-4 a pound. Just order a bag and in a few days you will have an abundance of duck hearts to play with! Thaw them just enough to separate them into ziplock bags with maybe 1/2 pound duck hearts in each, label the bags with the date and contents, and freeze......