Check out 180-mm artillery mount MK-3-180 mod 1938 Low-poly 3D model on CGTrader for $25. High-quality mesh by d2i: 10048 polys, 5277 vertices. PBR, Textured, UV Mapped.
BLEND (Blender, filesize: 1.46 MB), OBJ (OBJ, filesize: 678 KB), FBX (Autodesk FBX, filesize: 247 KB), GLTF (glTF, filesize: 278 KB), 3DS (3D Studio, filesize: 241 KB), DAE (Collada, filesize: 577 KB), USDZ (USDZ, filesize: 706 KB), ABC (Alembic, filesize: 556 KB)