Kongs are basically indestructible from what I’ve seen. We used to have a pittie with separation anxiety and a kong frozen full of peanut butter was good for hours.
Himalayan yak cheese/milk chew things - really durable, moreso than some of the bones we get. Our dog really isn’t into antlers, but my theory is that she likes the yak chews because they have an intrinsic flavor, and do actually wear down and give eventually. The only downside is that she likes to leave them in main walkways on light flooring, so I’m pretty sure I’m gonna die tripping over one, one day.
We also used to get chew rolls made from rawhide-alternative in bulk from Costco. They lasted a while, but we stopped getting them once we found the yak stuff, they get real gross.
(this sound bite lives rent free in my head)