I feed them raw.

My dogs always get bones outside because they can get a little messy.

For just a recreational bone (one your dog doesn't consume but just chews on) I would look for beef marrow bones or knuckles. They are usually labelled as soup bones in the grocery store. Strong chewers can consume these bones, but they are pretty safe for most dogs. As with anything it is best to supervise when giving bones.

Also when giving marrow bones for the first time I would cut off any extra fat on the bone and scoop the marrow out of both ends as it can be a little rich and may cause an upset belly.