I have a Western Field 550CD 20 GA with a C-Lect choke (basically a Mossberg 500, but made for Montgomery Ward back in the day) that is well over 30 years old. Does anyone know if it's worth anything? I only ask because I am planning on getting a new slug barrel/scope combo for it and maybe touching up the finish. I wouldn't want to re-blue or re-finish it if it's going to damage the value, but my sense is that it's value mostly lies in it's useability. Any info is greatly appreciated.