There are many one offs that have come out of the factory, i have seen some of them myself, the problem with this gun is if it doesn't letter then the seller needs to show the paperwork/work order etc which specifically references THAT serial number and clearly states that the stainless parts were authorized by the factory.
I may have to take a ride up to see the paper work myself, the UGB marking means that the gun was sold for less than normal retail…because it was a used gun (UGB=Used Gun Bank)
WE cannot even tell IF the serial number on the frame matches the label on the box, most likely it DOESN'T because the case is for a gun with a blued main frame and the revolver has a stainless main frame…that alone will tell the tale, IF the factory stamped the same serial number on a stainless frame and destroyed the blued frame…now that would be a unique one-of-a-kind revolver! However, the two hammers suggests after production changes, the grip panels could have been a one off sample, etc. The fact that they won't letter tells me that the employee was able to have 'repairs/work' done that normally the factory would NOT do for non-connected individuals. Unless the serial number is the same, this gun is just a conglomeration of factory parts for different model revolvers and NOT a special model that makes this a 2K revolver, but YMMV.
I don't believe that Chad has been up to Newport for twenty or so years! (But I could be wrong about that!)