Well I'd recommend feeding raw ALL the time. But, healthy treats include turkey gizzards, hearts, livers. (Any type of organ meat) I go to the grocery store and ask if they have any and get them for $0.38/lb, they are SO cheap! They dogs LOVE them and they are great for them. They aren't always in stock tho, so I like to buy in bulk when they are...but generally you have to ask for them they aren't always out in the store. Also I like to get soup bones that have some meat still on them and freeze them. Then on really hot days I'll give them to the puppies to chew on all afternoon. Those are around $1/lb. Hope this helps!
ADD: I have also made my own jerky for my dogs. I took beef heart (you can use any organ meat) and boiled it for a long time to cook it, then chopped it into tiny pieces, then baked it until completely dehydrated. It was GREAT for training and cost me $5 for a TON of treats!