bones from a butcher are fine. Some are edible and some are not. Weight bearing bones like marrow bones are one you can give, some people will not because there is a risk of teeth injury due to the hardness of the bone (i still give them, they are not edible but my dogs like chewing them). Rib bones are a good one (you can get them whole and they are pretty big) they are soft enough to be edible, any chicken or turkey bones, thats all i can think of right now
Bones are unsafe if they are cooked so make sure you give them raw. You could also look into antlers, they are safe and last quite a while but they are pricey and some dogs dont like them.