Yes, a new water pump and if the radiator is leaking from the damage, a new or reconditioned radiator. In the Uk at least these are easy to find. The good suppliers are Canley classics, james paddocks and others.
The parts are common to some spitfires too, which may make the search easier?
And I have never seen or heard of a water pump snapping. Yes, they can leak, but snapping? maybe just very very unlucky, or it has been hit/abused in the past.