I made it in Blender 2.82. I used the mirror modifier. I haven't rigged or animated it. It's just a turret. I tried to make PBR model.
STL (Stereolithography, filesize: 1.43 MB), OBJ (OBJ, filesize: 2.09 MB), FBX (Autodesk FBX, filesize: 868 KB), DAE (Collada, filesize: 1.87 MB), BLEND (Blender, filesize: 1.94 MB)