[steg]

You probably bought your Paterson from "JP" Petrizzo, who was hired by Lou Imperato to dispose of the Colt Blackpowder stock after he lost his manufacturing license from Colt.
The markings on the barrel are consistant with those on Italian reproduction Patrsons....I forgot which one. In all probability that gun was a pre-production sample to show what the assemled parts that Imperato was importing would look like after they were finished and blued.
The reason that your letter states that there were no records for this gun is that when production for Colt Blackpowder percussion revolvers ended, since there was no Federal serial number requirement they discarded all of their manufacturing records...possably to forstall any royalty arguments with Colt. No records, no proof!

 

[steg]

JP Reno is the shooting name of Mr. Petrizzo. When this gun was acquired, the staff at Colt Blackpowder was piecing together spare parts to make anything they could sell. I know, because I was in their factory and saw many anomolies being put together.
As for what it's worth, I would say not much more than a conventional, un-engraved 3rd generation Texas Paterson. The only thing that is different is the barrel marking, and there are not too many serious 3rd generation collectors to make it worth extra money. This gun will definately not fund your retirement. In fact, if you check asking prices for 3rd generation Colt Blackpowder guns as of late, their prices have been slipping over the past several months.
I know, because I have one of every model produced plus factory anomolities with letters for most of the models. All of these guns are factory cased with accoutrements.