I have a Holosun 507k Green Dot mounted on my Sig365. I have it sighted in just above the front sight. The green dot shows up very well. I recently purchased a Springfield Echelon which I am looking to mount the same Holosun on it. It has been suggested that a Vortex Defender-ST is a good fit...
Reading this article on the H-34 and seeing the photos brought back many memories for me. My first navy duty assignment was aboard the USS IWO JIMA LPH2. I worked the flight deck as a blue shirt aircraft handler. This was during Vietnam 1967-1968. I was aboard the Iwo when those shipboard photos...