I thought that but according to Wikipaedia they are a breed in their own right, slightly different to Chinese. See the link http://en.wikipedia.org/wiki/Swan_Goose
Swan Geese are a wild goose. They are the ancestors to the domestic Chinese and African geese. They look similar to a young african, but are smaller, not nearly as noisy and do not get the large knob on the forehead.
We lost our male this summer- so are considering selling our hen or finding a new male.
You might try contacting some waterfowl clubs in North Carolina. I bought all my mandarins from a man named Brian Daughtery. He is a member of the NC Waterfowl Club. Last time I was at his place he had over 60 species of waterfowl. He had swan geese, he said he was one of the few in the country breeding them. From memory he also had Teals,Cuban Tree Ducks, Shovlers,2 types swans,NA wood ducks,Austrailian wood ducks,Mandarins(normal and white),Swan Geese,Calls,Bar headed geese and many more I cannot remember. He ships. I will PM you if I find his number
The swan goose genus and species is Anser cygnoides ("cygnoides" is Greek for "swan-like"). The domestic Chinese goose is the same genus and species as well, but has just been bred in captivity for a long enough period that it has more "domestic" traits such as the white colored form (which I think was created in domestic geese through selective breeding). Genetically, though, I believe it's identical to the wild form.
The "African" goose, if I recall properly, is a fertile hybrid between Anser cygnoides and the European goose, Anser anser. Same genus but different species, but can cross-breed without sterility (like a coyote and a wolf).