I'm fairly certain that stock has been stripped down, and the checkering possibly re-cut (although certainly not badly--on my two '20s vintage Mannlichers, the original checkering is noticeably shoddy in comparison to the overall workmanship). Using a ruler against the Gunbroker photos, plus my standard 1903 carbine's bbl length as an index, I'd also extrapolate a length just under twenty inches on the Gunbroker gun. I'm hoping you get pictures up, just because they'd be fun to look at. I intend to post photos of my rifles soon, as each differs in unique ways from everything else currently logged on this forum. By the way, have you run your serial # on Griffin and Howe's online research index? If your gun ever passed through their shop, you may be able to learn some interesting provenance. Good luck--