I'm not sure, but it seems doubtful.. those gun holsters are for long barreled Time Crisis-style guns with some size and weight to them.. the Act-Labs guns would probably drop into the bottom or in the very least not fit comfortably because they're so small..
Somebody had made a damn nice holster out of craft leather and then cured it.. probably only way to get a perfect size and fit.
I'm still hoping to hack my GunCon so I can also use this type of holster.. my Jap version (from way back) is even molded in black plastic with red buttons

<queues up some Alice Cooper>