Water pump rattle ?

[TX '90 ZR1]

Bringing this thread to a conclusion.
Ordered parts (water pump, hoses, clamps, gaskets,) from our favorite parts supplier, Jerry's. Upon removal of the water pump it was obvious it was the culprit causing the rattling sound. The shaft had a bit of play and the noise was being created by the impeller making intermittent contact with the housing. The pump was NOT leaking and showed no signs of previous coolant leakage.
Thanks for everyone's input.