Scout:  The marking, ('carving'), you are referring to is actually the Cartouche Stamp, "J.S.A. 1900" in a rounded box.  This stamp was put on a completed U.S. arm upon acceptance for service (J. S. Adams - Inspector).  The other stamp is probably a stylized letter "P" in a circle behind the trigger guard.  This notes the arm has been 'Proofed' (proof rounds fired in barrel).  Stocks have been switched around on a lot of Krags, since Springfield Armory issued them.  Nowadays, stock markings do not always agree with the production year of the arm.  It is desirable when they do.  A lot of Krags have stocks without a Cartouche on the left side.  These are considered 'Field' replacements, done outside the armory for repair.

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