HDRI Panoramic Sky - 360 - rainbow sky Low-poly (Polygon mesh 3D model) is available on CGTrader for $15. Original author: TastyVoxel. Specs: 2880 polys, 2802 verts.
STL (Stereolithography, filesize: 274 KB), OBJ (OBJ, filesize: 374 KB), BLEND (Blender, filesize: 1.13 MB), FBX (Autodesk FBX, filesize: 149 KB), DAE (Collada, filesize: 726 KB), ABC (Alembic, filesize: 160 KB), GLTF (glTF, filesize: 128 KB)