Quote: It is not. The taihe chicken has white silkied plumage (a stark contrast to the black skin, meat and bones), and originates in the mountains of China. It has existed there for several thousand years.
As for the cemani, serious breeders are willing to pay serious prices for bringing new breeds to the US. It is extremely expensive to import birds, therefore the cost of eggs, juveniles and breeding pairs are quite expensive for the first several years. When serama were originally imported they, too sold for huge sums. It has been long enough now that their prices are in the range that almost all breeders would consider reasonable.