Well- been here myself.
I bought a really nice Airsoft Luger navy replica from Mike at Elite Shooting some years back before the stupid VCR rules were enforced. A very realistic replica but shoots 6mm airsoft shot.
Last year I bought a KWC BB blowback replica from my local dealer.
It's good- very good. The detail and construction is excellent. It strips just like the real steel (in fairness so did the airsoft pistol) The grips are plastic, but I've bought some wood grips from India of all places, these will need a bit work on the inside to make fit but it's doable. The pistol itself has a very brisk blowback action, so much so you are hardly aware of it- probably like the real thing considering a fairly substantial bit of engineering is doing its thing in front of your face. Impressively scary- let someone else shoot it and watch from the side.
Inho you have to buy a blowback Luger- nothing else captures the whole point of it.
Oh and before you ask- is it accurate? Sorry- not relevant, the pleasure is in the design and function. It MAY hit a can at 10yds- but frankly who cares