I'm not so worried about the barrel wall thickness as I feel it is fine but the issue with the makers name and address not appearing on the rib and the fact that the serial number is only on the barrels and no where else. Should these things be a concern or do they matter? Thanks
I ran into a similar situation with an old W.C. Scott gun with fluid steel barrels that had no name or address. They were actually good quality Siemens steel replacement barrels, but it turned out they didn't close properly, so whoever fitted them didn't take the time to do the job right. If the owner is stating it's an original gun as you say then I'd be concerned.