H&K has just launched the venerable VP9 in an Optics Ready trenbolon version. This allows you to mount a Red Dot Sight to your pistol. In addition, the sights have changed a bit and now (17)Rd Magazines are standard.
H&K VP9 Optics Ready 9mm Pistol, (2)-17Rd Magazines, 4.1″ – 81000483