I obtained this Model 41 a number of years ago out of a collection. I never did start shooting it as I had others I use regularly and this became a safe queen. Well, its time to starting parting with things and I need a little help with history and value. The serial number is 91xxx, which I think places it as late 1960's production. There is a muzzle brake and extra mags. A second barrel came with this gun, and I think it matches the descriptions I've found on these forums for a "Light Field Barrel". I've attached a couple of photos to help with your review. Thanks for any help you can provide.