Hey K-Heres an idea I do.

Buy some liver at the grocery store or meat market and dehydrate it. It is relatively inexpensive.
Cut it into strips and lay it on a tray and let it dry until it has a jerky like texture. Our dogs love them.

One word of warning. It might be best to dry it in the garage or on your deck outside. If you don't like the smell of liver, it will make your house stink for days. Believe me I learned the hard way the first time.