Check out RailScales M-LOK Railcovers Low-poly 3D model on CGTrader for $12. High-quality mesh by Sided: 536 polys, 270 vertices. PBR, Textured, UV Mapped.
OBJ (OBJ, filesize: 82.7 KB), FBX (Autodesk FBX, filesize: 340 KB), BLEND (Blender, filesize: 207 KB), TEXTURES (Textures, filesize: 642 MB)