I also feed cow knuckles and find that my dog's teeth are generally clean- certainly not needing cleaning under anesthesia. And cow knuckles are pretty cheap. About $4 each from my supermarket.
Here in Indy, about 3 years ago I was quoted around $500 for teeth cleaning (including anesthesia).
So I guess that my vet is not terribly out of line on the cost, anyway?
In No. CA.