Looks like a MT1 spur there. MT2 should work, and it has a slipper. You may have to use MT1 drive cups to fit the center dogbones correctly. Get the instructions from HPI for the MT1 and MT2 18SS. If you are replacing parts anyway, it would be a good idea to upgrade to the 18SS parts for the drivetrain, to hold up to the brushless power. Most MT2 parts will fit, some may require modifications.