What is a fair price for a Colt Government Mark IV Series 80...Blued finish? Less than two clips fired through it. Bought new about 15 years ago, and after initial test firing, it has been sitting in the box. Have original wood grips as well as Pachmeyer grips. Only the one clip that came with the gun. Also have a Bianchi holster to go with it. What would be a fair price or trade value?