A good look at the Slong TMB Venom PDW Kit in this video by Jeidanten. The SLONG TMB Venom PDW kit is an upgrade for various airsoft pistols, including VFC PPQ NPA, VFC M17, VFC M18, VFC GLOCK, and WE GLOCK models (with minor modifications). This deluxe version comes with a buttstock and AR grip for enhanced stability and control. A simplified version is also available for those seeking a more streamlined setup.
SRU, busy thinking of new kits for airsoft, got something that Hi-Capa GBB users would welcome as an option kit, a PDW Kit. This kit is designed for the 5.1 and 4.3 Hi-Capa GBB Pistols from Tokyo Marui, KJ Works, WE Airsoft, and AW Custom. This allows you to have a more stable platform with your pistol especially for close quarters airsoft battles.
The Liberator Gunshop, an airsoft shop in Osaka, Japan, shows the SRU Glock PDW Conversion kit.... "This is a conversion kit that you can easily change the Glock to PDW-style with stock. Because it can be easily done with a a few screws, even people who will customize for the first time assemble it easily. Pay attention to the screw as it is the only part that you might easily lose."