I might be looking for one as well, but I'm more concerned with durability, as I've had a few air pistols before I switched to blank pistols and all of them broke after 2 years of occasional use - some even earlier than that. All air pistols I've had used were CO2 powered and after they all broke down I gave up on them, even though I took GREAT care of them...
With my Crosman Vigilante (a 357 variant with a cheaply made bull-type shroud for mounting accessories) I always put some silicone oil on the co2 capsule and even ran some maintenance capsules from Walther every once in a while. The gun eventually ceased to work altogether, when the iron tube/barrel came loose within the shroud and is now causing misfeeds, also the valve seems to have gone.
My first air pistol was a Valtro 92, with a double rotary magazine system that takes pellets... the gun only lasted some 3 months, before the valve broke and started leaking co2. It was a really fun gun, but now the notches within the magazine don't even fixate the capsules anymore... Just a bad gun overall.
I also had an ASG/CZ replica on which the seals failed and were once again leaking co2 - I managed to sell that piece, but I still have the Crosman and the Valtro.
If you're in the US of A, just get a flobert pistol and enjoy... In my country only the privileged can own firearms - and I'm not one of them.