Just a heads up, no responsible breeder will allow a puppy to leave their home at 6 weeks.
Try checking here for a breeder of merit in your area: https://www.basenji.org/joomla/index.php?option=com_content&view=category&layout=blog&id=111&Itemid=94
I second Crazysenji…....
The dogs I meet, that have major behavioral issues, when I'm out walking my dogs, ..... all were separated at 6 weeks. The only puppies I've heard of being separated at 6 weeks 'responsibly' were being trained for major k9 police work and weren't being taken away lightly.
BTW 100% bladder control isn't physically possible until a puppy reaches 6 months anyways....so getting a puppy too early is a moot point. I got my newest pup at about 3 months and there were no bonding issues.
Just letting you know that breeders or rescues are going to balk a little if you want a puppy at 6 weeks.
Your best routes for puppies:
Basenji Club of America has a breeder referral list on their website - some of the breeders post litter announcements, some of them you have to call. OR look for a basenji club in your state...or hound clubs sometimes have litter announcements. Some of them are willing to ship.
I've seen a couple different rescues have puppies available: Basenji Rescue and Transport, as well as the other ones like colorado basenji rescue. The issue with those is that they usually have waiting lists + the home inspections + not able to ship.
Petfinder/craiglists can be a good option if you know how to differentiate between scams and legitimate posts. I never see a lot of purebred basenji puppies on either one though. Mostly adults, or mixed breed puppies (if that's an option for you).