the 25-20 is basically in the same class as the 22 hornet. In a pinch in the past it has been used on white tail, but really it's best off shooting pretty much the same critters as you'd probably use a 22LR on. Possum, coon, rabbit, javelina, porcupine, whatever.
So before I'd consider getting that rifle I'd consider the chambering. It's one you are going to have to hand-load, very little factory 25-20 is still floating around. Plus those cases are notoriously fragile, they tend to take a ding or dent really easy, so while the priced of the powder to fill that little cartridge up isn't much, they can be a bit of a head-ache to work with.
In the end a gun for this chambering is a real soft shooter and easy on the ears too. For just a fun shooter IF you are the kind of guy who really likes to tinker around as he reloads, I think it would be fun. For anyone else, no.
As far as the price range, it really depends on the age range that the 92 is in as well as condition, and if it is in an unusual combination.
I.E. I don't think anyone is going to be able to give you anything close to a solid answer until you have a bit more information.