Where did you find the NM sights? I am also looking to upgrade my m305 polytech iron sights.
Thank you
The website is on post #12. For 25$ I only got the rear aperture. If you want the complete rear sight assembly it might be over 100$. For 25$ the NM front sight included the screw.
NM sights are really accurate. With a good eyesight, you'll be surprised of your grouping at 2-300m.