Persona 3: Evoker (rectangle upper receiver)

I made this model a while back, way before the new Person 3 movies. My references pictures were really bad so I couldn't tell if it was a square or circular upper reciever so I just made the easier one. I would make a circular one, but since my SolidWorks student liscence is drying up soon I may have to make the switch to Blender (a switch I should have done awhile ago). Anyways this is obviously the Persona 3 staple "weapon" the evoker. I have a version with shitty textures, but I would rather not subject anyone to my poor texture work, so this is just an untextured version. The cartridge ejection port is all distorted because of the conversion to .stl (honestly I don't even know why it's there since the gun doesn't shoot bullets).