We've just released 15mm Jurchen as opponents for our popular Sung Chinese range. It's a complete range for the Jurchen Jin dynasty who were the epic foes of the Sung, in the century before the Mongols came and swept both dynasties away. The Jurchen were Manchurian horse warriors who overthrew their Khitan Liao overlords and established their own dynasty in the north of China.
There are seven codes available -- two of them, Chinese unarmoured crossbows and Chines unarmoured swordsmen, would be equally useful for the Sung range. Available now: http://khurasanminiatures.tripod.com/jurchen.html
A few samples: