I'm a Pennsylvanian and unfortunately the state is infamous for its puppy mills; some are operated by Amish farmers who live in Lancaster County.
If you drive the Pennsylvania Turnpike from the Philadelphia region to Lancaster County there is a huge billboard 0_1547047988771_mills.PNG saying "Welcome to scenic Lancaster County, land of Puppymills" that that has been paid for by a wealthy Pennsylvanian sympathetic to the plight of these dogs.
Some farmers will have their children sit by the roadside near their farm with a basket of puppies (and who can resist a child with a puppy?) and the prospective buyer does not get to see the stacked cages of poorly maintained dogs of all breeds that are used to keep this business going. Simply put, the Amish regard dogs as livestock and a revenue generator.
I would take the advice of the members of this forum. Also check the Basenji Club of America website for a list of breeders and the American Kennel Club (AKC) website.