I was in my LGS last week and was looking at a nice long frame super. Nice high polish blue with a little holster wear at the muzzle and on the ejector rod housing. It had after market stag grips that were a little fat with lots of bark. I have a question about the serial number. I have read that the highest known serial number for a long frame is 3100 or so. The serial number on this gun is 407x. My question is my research wrong or is this out of the known serial number range.