A friend of my son gave him a winchester model 12 pump in 16 gauge. He doesn't hunt or shoot,so he asked me if I wanted it free of charge? I said hell yes. Now my question. It has some small rust spots on it and problely needs to be reblued,but it seems to funtion ok.It is a 2 3/4 inch,full choke and I can't find a serial # anywhere.Does anyone have any idea how much it is worth? thanks sj