About this 3D model

This is my take on the standard steampunk super trooper big boy gun, and it is way too big. Models stockhttps://www.thingiverse.com/thing:2616451 toggle lockhttps://www.thingiverse.com/thing:3949991 Ammohttps://www.thingiverse.com/thing:3457310 magazine ???????? please tell me I lost the original file