RE: sighting system for pistol caliber carbine.....
IMO a nice toy if you already have a 92.
Any good red dot will do , I would not use a cheap one ( less than $80 )
I would sight it in at 50 or 75 yds
With the current prices of guns and ammo I would go with a 16" AR15
Surplus 223 is cheaper than 9mm most of the time
Johnch