I get some at the grocery store. Cheaper than the pet store. I got a leg bone from the grocery store butcher and they sliced it for me. It only cost $2.80 (something like that, less than $3) I was just going to get a rack of ribs and slice them up myself.
Maybe try chicken wings/drumettes. They go pretty fast so no teeth benefit. They get one in the afternoon or before bedtime sometimes as I feed once a day in the morning.