Which air pistol for live firearms practice?

Price Range: $100-$300

Type of Gun: preferably CO2 (availability wise), electric and spring will do

Preferred Gun Models: m9 etc. (any pistol with a functioning -internal or external- hammer for single action)

Role: trigger and accuracy practice for live firearms (specifically 9mm pistol).

I need an airsoft (6mm) or airgun (4,5 mm) pistol that's for low rate of fire, off-hand practice shooting. I "primarily" need a very realistic trigger, blowback isn't necessary since I don't mind cocking the hammer every single time and I don't care about recoil, but it should eventually be capable of single action. Secondary feature would be accuracy downrange, therefore decent fps wouldn't hurt, for the same purpose. Tertiary, realistic weight and ruggedness, preferably full metal. Thanks in advance for your time and knowledge.
 
I guess I do a different take on replica air pistol-firearms practice. I chose a CZ Compact BB CO2 pistol to replicate my 9 mm CZ PCR. Why? They are exactly the same dimensions and frame size. The familiarity in handling the CO2 pistol directly translates to handling the 9mm CZ. They carry the same, point the same,load the same with clip, and handle the same(close to the same weight). Because of this I can now shoot my CZ 9mm either right or left handed, load it much faster, and are a lot more comfortable carrying it after carrying the CZ CO2 pistol.

Does it shoot the same? No air pistol on the planet shoots the same as a 9mm so I don’t try to replicate that side of it. The CZ Compact is only $49 and is a true auto with spring fed BBs instead of cylinder fed like many replica autos that are really revolvers. It’s not a blowback(which saves air) but you can rack the slide, and shoot it either single or double action. So I would try to replicate the same dimensions and function over accuracy in an air pistol for live firearms practice. 
 
"Gunnertrones"As EM rider stated. Weihrauch HW 45. 
Check out this video on YouTube:

I have one in black and one in silver. The black is a bit cheaper, and actually the one I prefer. The silver coated one isn't to my liking, but both preformes the same of course.
I have owned a few HW45/P1 and while they feel like a firearm, the hold needed to shoot them accurately is a loose hold and leads to bad habits when transitioning to firearms.
 
I use a Umarex Colt Commander for practice drills. Runs exacly like my Colt 1911s except the mag needs to be pulled out, it doesn't drop free like the real thing. With a spare mag, double tap and reload drills are a blast. I haven't ever bench rested it, 1.5" targets at 7-10 yards are easy on the run. They probably make one that will match your pistol.