really depends on your location and what people around there think they're worth. I know some folks that would pay a pretty penny. But I also know some great spots to find ENORMOUS antler sheds in the mountains and wouldn't give a dollar for them.
Try putting an ad in the paper for 100 bucks, if it's a mountable clean set, unbroken, I'd bet they would sell.
I saw a huge rack in sportsmans warehouse the other day... . now this was FAKE, not real, man made rack and they wanted 1000 bucks. I couldn't believe it. People must be made of money to have that kind of crap hanging on their wall for a cool grand.