After the cassoulet discussion a few days ago, it occured to me to check out an online French product site that I have had luck with in the past, called Joie de Vivre. They sell duck legs in 5-pound portions for $25 and 2-pound tubs of duck fat for $10. Already-made confit is about twice that price.
I haven't bought either of these items from them, but with other purchases have experienced good, friendly customer service. They don't have Tarbais beans listed but may be able to point out a good source.