Check out southeasttexas.com, type in goose or geese in the search area, if you don't see one post "goose wanted "in the farm or livestock section thats how i found my peachicks.
I saw an add for some for sale in lumberton last month i think they always got something for sale ,never been there so i don't know what kind of living conditions they are in.
Let me know if ya don't have any luck, i live close to you near beaumont and i know someone that did have geese for sale a while back
i can give them a call.