Ruger records finally got back to me. This gun shipped March 1962. The invoice for this gun does not have a price on it . Chad mentioned if it was shipped with a box you could tell from the price, makes sense. Unfortunately not all invoices have a price and this one didn't. Additionally I'm told that even guns with the boxes were shipped as a package with no notation on the invoice that a box was included. Odd but true I guess. Based on this, no mahogany cased gun should letter unless it happen to have the higher price on the invoice. Does anybody have one with a factory letter and if so how did the factory verify it?. Chad's Reference mentions a SN close to mine as the highest known ( SN 8650) and is stated as such because the original owner verified it. Taking nothing away from Chad's data, technically that is just hearsay or could be. I don't know the details of who the original owner was nor do I doubt its truth but without a letter it's still hearsay. Also, the original owner of my gun is no longer with us.