Schlingmann VARUS Castra Back Construction (Polygon mesh 3D model) is available on CGTrader for $20. Original author: BlueLight-3Dx. Specs: 1247552 polys, 792247 verts.
OBJ (OBJ, filesize: 17.7 MB), FBX (Autodesk FBX, filesize: 28.2 MB), BLEND (Blender, filesize: 96.8 MB)