The sights are a "gutter" in the top of the slide. It's sort of like looking at the sights on an old S&W J frame. Just a groove.
Designed for no snag draws, and ultimate concealment, and up close and personal "business". Most of the time, under duress, point shooting is used anyway. But they do work. Just takes a little getting used to when shooting at paper targets.
The only place I can find this is on lipseys web-site, but it is a TALO edition of the New Agent, COO7812DXS It has:
Grip:Unique Tactical Colt Logo Grip
Sights:XS Big Dot Tritium Night Front
XS Express White Line Rear Sgt
As I write this, they have 25 in stock vs 17 of the none Talo shown above.
I'm not sure the following picture will show up or not. I have a cookie for Lipsey's web-site, and it may be letting me link to pages that aren't available to the general public. If it doesn't show up, let me know and I'll put it somewhere available to all, but I'd like to know if this works for future threads/posts.