They were made in Italy by Uberti, pastr finished and assembeled by Iver Johnson, marked and marketed as Colts.
They have become very collectable over the years. The better the condition, the higher the value -unfired and in the box is very good, but I can't give you a dollar figure, either.
Last one I saw for sale was nearly 10 years ago, and for some reason $700 comes to mind, but I'd check some of the auction sites and try to find a similar one for sale to get a rough idea.
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