$15 Medieval Mill Low-poly 3D model by ZoryaCG. Available on CGTrader with 7077 polys and 8372 vertices. Check it out on CGHub.
STL (Stereolithography, filesize: 692 KB), OBJ (OBJ, filesize: 1.09 MB), FBX (Autodesk FBX, filesize: 387 KB), BLEND (Blender, filesize: 2.21 MB)