I stumbled over the seeming numeral inconsistencies too, but taking the dominant direction of illumination into consideration, I finally decided that they were the same number. I am pretty sure the fourth digit is a 1, the next a 6, and the last an 8. I have had trouble with these deep-stamped blocky numbers before, but if you can move your angle of illumination around you will eventually see that only one numeral is likeliest.
I have had guns struck so deeply that I could not tell for a long time if some numerals I was trying to discern were a 3, 5, 6, 8 or 9!
I also believe the stocks carry the same number I see on the forestrap and the cylinder, though since the impressions are in wood the chance exists for a different type of deformation.
At least the 530 portion is clear on all parts!
Rich, you are the only one who can give the gun a close inspection. Can you look at the numbers on the stocks, frame and cylinder and let us know if they are the same? In case you are a glutton for punishment, the same number should be found on the underside of the ejector star and on the short face of the crane that is parallel to the front face of the cylinder. You may be able to read that one with side lighting while you peer through one charge hole.