The best toys I've found for champion chewers is Kong toys. They have some really great ones at Petco, Petsmart or even online. Red for medium chewers and black for champions.
They don't have squeekers in them, but you can put the kong stuff in them and they'll spend hours working on them. I use liver paste.

My grandpuppies get black ones. They can destroy stuffies in a matter of minutes.