The TR water pump is big hefty casting, and if the pulley is hitting this it is probably indicative of worn bearings.
If you can do a temporary fix wish a couple of washers on the pump then great , but before doing any significant mileage I would be inclined to take the pump off , and get new bearings and seals installed in it.
If the noise proves not to come from this area , then check the fan on the front of the dynamo, or indeed check all the mounting bolts that secure the dynamo. The front lower mount in particular tends to strip threads, allowing the dynamo to move out of alignment.
Unless you are a sticky for originality an electric fan behind the grille works well with these engines
