Just a decent bash-plate will do. Mine was 'tested' in many crashes (also on hard rocks) but it's unlikely that the pump will be torn off: there's only one registered example I know of (picture is somewhere on this forum).
Look at these pics where I'd hit wooden pole at 50km/u:
notice there's a piece of wood penetrated the coolant tube. The bash plate has a dent where it hit the pole.
Pole didn't stand as well:
HJ