If it has the box, which seems original, with the S&W label, which seems original, wouldn't this confirm more or less, this is a special order item made by S&W and not an aftermarket job?
I have purchased before from Simpson, and from my understanding, they put their mark on all of their firearms when sold and shipped out.
I have purchased before from Simpson, and from my understanding, they put their mark on all of their firearms when sold and shipped out.