
You should have no trouble finding a reputable breeder of chows if you contact the breed club, not sure what the annual registraion figures are, but if there are no pups currently then get yoru name on a waiting list.
Never ever buy from a dealer/pet shop, as the breeders of such pups have no interest in the breeds, pups or your welfare.
If you Search this site you should be able to find the breed clubs listed, failing that go to the Kennel club website, click breed standartrds, then utility, then chow and at the bottom are the contacts for the various breed clubs.