barbell and bench 3D model is available on CGTrader for $5. Original author: nao5970.
3DM (Rhinoceros 3D, filesize: 5.86 MB), OBJ (OBJ, filesize: 5.19 MB), MAX (Autodesk 3ds Max, filesize: 6.52 MB), STP (STEP, filesize: 1.94 MB), BIP (KeyShot, filesize: 2.74 MB)