Holosun HE509T X2 Low-poly 3D model is available on CGTrader for $5. Original author: Akinaro. Specs: 4533 polys, 2559 verts.
BLEND (Blender, filesize: 75.4 MB), BLEND (Blender, filesize: 75.4 MB), OBJ (OBJ, filesize: 75.5 MB), FBX (Autodesk FBX, filesize: 75.4 MB), DAE (Collada, filesize: 75.8 MB)