This is a T-14 that was reworked in the Mukden arsenal.  When the Japanese occupied Manchuria they took over the Chinese Mukden arsenal and made rifles and bayonets.  What is little known is that, although they didn't manufacturer them, they reworked T-14 pistols.  This is the only example that I have observed and I have heard of one other.  The gun is totally matching including the grips and the magazine.