But many shelters/rescues have an acknowledged habit of listing dogs as mixes if (a) they aren't entirely certain it's a purebred or (b) if it's a breed that can be difficult to place and listing it as a mix may make it more likely to be adopted.
IN-Indianapolis-Young Male Brindle B Mix-In Shelter
This boy looks mostly B! He is in the Indianapolis Animal Care & Contol shelter. He has good comments from the shelter and his adoption fee is only $60. I have not contacted the shelter to see if he is still available. I have not sent the info to BRAT.
Here is his Petfinder page: