Good thing you asked!
SIG P226 sights will not fit your NP-22, lots of posting about that.
You can always glue them in:
http://www.canadiangunnutz.com/forum/showthread.php?t=694204&highlight=norinco+sights
OR, you can take your NP-22 to any gunsmith and see about fitting some adjustable sights that he may have left over and cheap. Installed, you may get away with spending less than you would on the wrong, non-fitting P226 sights.