I agree if Mark had not provenanced this I would have ignored it as a fake(and even refused to sit with him at our next Timonium luch!!
), but there seems to be enough evidence here...and just enough oddity to it...to back up the story. I think what to us may seem 'tacky' or crude(fittings, etc.) may have seemed exotic and rare to the Siamese....with that it mind it makes perfect since to me that from their perspective they were sending the President a rare and exotic gift.
The lack of patina here does not really bother me, afterall, this was probably accepted, cataloged, and stowed away, and I am betting it was actually handled very few times...probably more by museum folks than in the 19 Cent.
The thing that I find so fascinating and appealing about it is....what I love about that entire SE Asian region weapons-wise.... and that is the clear fusion of so many different cultures. In this case it may not have produced the most beautiful product, but just the attempt I find interesting.