I get beef and pork ribs from the butcher. I raise my own goats(and now a steer too). I also order from Hare Today and My Pet Carnivore.
Your GSD will chew them up, and then because they are NOT cooked, he will digest the pieces. To start with, you do have to keep a close eye on your dog to make sure they actually gnaw instead of trying to gulp the whole thing, so it is best to start with bones that are really too big for him to even think that he can swallow them. He will learn than he has to eat them instead of gulping. Some people have had to try tricks to slow their dog down, like attaching vise grips, but that isn’t common.
All cooked bones are dangerous. They will definitely splinter. Chewing raw bones will definitely help clean his teeth, though he may prefer to chew on one side more than another and you may have to hold a bone so that he has to chew on the other side. I used to have to do this with one of mine, but somewhere along the way I no longer have to do that.
