I'm not sure where to start trying to look without having a serial number on the box?
One thing you can do is watch the high end auction Websites like Rock Island Auctions. They have many high end guns that are often in original boxes so that could give you additional data points for comparison. The SCS&W is a great reference packed with a ton of valuable information. However it is NOT ALWAYS 100% accurate and it gets updated from time to time as new discoveries are made. I'm not saying it's wrong on this issue; I'm just saying it never hurts to make your own analysis.