I've played with the cartouche pic a bit, and I am satisfied that the last digit is definitely an "8". This leads to two conclusions - either the stock is not original to the rifle, or, if is, the receiver must have been held up for awhile - perhaps it got shuffled to the bottom of the bin, or got kicked under a bench? We will never know, but it is a very handsome rifle and I wouldn't worry terribly about the mismatch.