Wouldn't be that hard to recover with a rotator wrecker, especially since it's a small single axle truck. I helped out on one kind of like that about a year ago on a single axle dump. Got stuck a little different however, that one had gotten the top edge of the bed stuck in a metal rail instead of being held by a tire.
I would be interesting to know if the tire held up until a wrecker got there or if it took the plunge.