This time of your from a responsible breeder you will be hard pressed to find an available puppy, most all responsible breeders have full reservation list for any pups that they had this past year (2020/2021). Please be sure that you check out health testing if you happen to find a puppy... And I would suggest that you contact breeders in the PNW for possible pups for the Fall/Winter of 2021
The only place I know in the UK that actually requests copies of health certificates from breeders is www.champdogs.co.uk
I am sure if there are other sites and or places someone will be quick to correct me, but this is the only one I know.
Hope that helps.
Contact the breeders from the Basenji Club of Great Britain:
http://basenjiclubofgb.org/breeders.php
I agree with wizard, males and females have various temperaments.
http://www.coloradobasenjirescue.org/adoptable.shtml
Co basenji rescue has several young-ish dogs looking for homes. And those basenji/terrier mixes are adorable!