May I cross post this to another basenji chat list? The more people know, the more likely she will be found.
Put up flyers all over, with her photo. They can be 3 miles away in a heartbeat, so go as far as you think she may have gone, then go another mile or so. Let all mail carriers (or other delivery people) in the area know, and keep searching, with other basenjis if you have them to help. It will show people what kind of dog you are looking for, and she may come to another dog and not to her humans, they get really spooky when they are lost.
Put a notice in every paper or 'add flyer' and keep them there, I know of several dogs that were found after being out for a month. Enlist kids that are out of school and 'out and about' in the areal
.
Good luck, a lost basenji is a nightmare for us all.
Anne in Tampa