Check out LA-K12 Puma Bullup Shotgun PBR Low Poly Low-poly 3D model on CGTrader for $29. High-quality mesh by Polygate: 17611 polys, 16146 vertices. PBR, Textured, UV Mapped.
OBJ (OBJ, filesize: 92.4 MB), FBX (Autodesk FBX, filesize: 1.87 MB), 3DS (3D Studio, filesize: 1.27 MB), TEXTURES (Textures, filesize: 89.4 MB), MEL (Maya Mel Script, filesize: 89.4 MB), MAX (Autodesk 3ds Max, filesize: 10.2 MB), C4D (Cinema 4D, filesize: 2.74 MB), MA (Autodesk Maya, filesize: 2.18 MB), BLEND (Blender, filesize: 3.21 MB)