Originally destined to be an 03a3 but due to a shortage of rear sights the rear bridge was milled down to mostly remove the sight base and the rifle was completed as a regular 03. Nice rifle and I’m not sure that’s the wrong stock.
I have one of these "transition" 03's as well. Curious what parts are on it. Is your lower and upper band stamped with an "R"? Mine had a Springfield replacement barrel on it one month behind the serial number of the rifle.