Check out Australopithecus skull and skeleton Low-poly 3D model purchase 3D model on CGTrader for $2. High-quality mesh by OttosLabs. PBR, Textured.
BLEND (Blender, filesize: 2.5 MB), OBJ (OBJ, filesize: 1.48 MB), FBX (Autodesk FBX, filesize: 798 KB), DAE (Collada, filesize: 2.35 MB), STL (Stereolithography, filesize: 879 KB)