Check out ZPU-4 machine gun 3D model on CGTrader for $119. High-quality Subdivision ready mesh by MrFrezzy: 758380 polys, 762159 vertices.
OBJ (OBJ, filesize: 16.6 MB), BLEND (Blender, filesize: 23.9 MB), 3DS (3D Studio, filesize: 3.84 MB), MA (Autodesk Maya, filesize: 16.7 MB), MEL (Maya Mel Script, filesize: 16.7 MB), MAX (Autodesk 3ds Max, filesize: 68.7 MB), C4D (Cinema 4D, filesize: 9.94 MB), FBX (Autodesk FBX, filesize: 29.8 MB)