I think you're going to have a hard time finding stag at that price range. Inexpensive knives imported with stag handles are going to trend towards stainless. So you may have to compromise.
Boker may have something in the Arbolito line (made in Argentina) that interests you. Not sure, but I think they're all stainless though.
Muela from Spain is also in your price range. Stainless.
Some of the Chinese import brands offer stag bowies as well. Never seen one in carbon steel though. Hen and Rooster, Marbles, etc.