I say just go there and tell them that you are moving and that you love them and that you really going to miss them and you really need their recipe to survive in the wilderness, or arctick. And just start crying and begging, it might work, you never know.
Funny! I had posted about this on Facebook, and a friend from the old neighborhood actually went there and got some for dinner tonight. She asked for the recipe but they will not release it. It's pretty tightly guarded secret, since 1958!