It's an airsoft bb gun. I bought it many years ago on Ebay. I don't think they make them like this anymore. It even has the Beretta logo on the handle.
The shirt is a Barnys of New York, the holster rig is a galco *******/Miami left hand beretta 92fs, when looking make sure the straps are fatter on the shoulders and make sure the back matches up to McClane’s (leather should stick out above back piece a bit check reference photos when looking). So far nobody has been able to find the correct shirt that I know of for sale, and the galco rig pops up time to time but is usually quite expensive