HK USP 45 Auto Low-poly 3D model is available on CGTrader for $42. Original author: PHR-Workshop. Specs: 5171 polys, 2629 verts.
BLEND (Blender, filesize: 264 KB), OBJ (OBJ, filesize: 112 KB), FBX (Autodesk FBX, filesize: 681 KB), TEXTURES (Textures, filesize: 188 MB), SPP (Substance Painter, filesize: 407 MB)