I don't think there are any US hatcheries that would be sellin' anything like that EXCEPT single-combed wyandottes, which are not especially uncommon especially from certain hatcheries. It is a recessive gene and thus difficult to entirely eliminate, plus I think I've read there is some reason involving fertility for keeping it in the gene pool.
So I will betcha ANYTHING that what you've got are simply single-combed SLW's.
Good luck,
Pat