Glad to hear he's recovering well!
I'm new at offering Zippy Bully Sticks. These are the only ones I've tried:
Redbarn Bully Sticks 5" Dog Treats, 5-in chew, 1 count
Redbarn Bully Sticks 5" Dog Treats
The first 2 I gave him lasted a long time and were nearly full length when i threw them away. The third one I gave him only lasted a couple days before he chewed it short and I threw the stub away.