I have a like new in the box 338MX Serial number 91029xxx. It has a "JM" on the barrel. I won it at a charity auction three years ago and put it in the closet. I am not a hunter so I want to sell it. Never fired, never unlocked. As far as I know it was only out of the bag on display at the auction for a few hours. Should I put it on GunBroker or TexasGunTrader? Any help how to sell is appreciated.