Weatherby XXII question

Gentlemen,I just purchassed an XXII Japan clip model with what I consider an unusual stock variation. This is the only one that I have seen fron Japan to have a solid stock without the rosewood end cap and pistol grip cap. This stock is all one piece. I have an early Italian solid stock model and thought that the stocks were the same but they are not. This Japan stock seems to have the same finished contours as the rosewood type, but one piece, where the Italian early gun has a different flair at the pistol grip. What gives? Both stocks have the metal buttplate.Any insight on this or any other XXII history is most appreciated.