Water Pump Question

[rmmagow]

83 300D.
Can a water pump wear out its impellers without wearing out the bearings first? No signs of leakage. The car runs a little hot but if I turn on the heat (no fan, just crank the wheel to max) it will drop to just a shade over the 80 C mark the same as my other 300D. I changed coolant last summer and even the old coolant didn't look too bad. As best I can tell the rad's not plugged. It will run up to just over 100C and more or less hold there. I'm pretty sure I'm seeing "real" heat as the oil pressure is lower at idle when the temps up high, about 1.5 on the guage whereas if the temps reading near the eighty mark the oil pressure is much closer to 2 at idle. Thermostat was replaed too as were the belts.
How much broken off bolt risk is there in removing the water pump?

Thanks for any advice.