Water pump - DIY? How much is fair to PAY to get it fixed?

[23109VC]

My car was at my independent mechanic today to fix a vacuum leak. It's so nice to NOT have that nasty hissing sound as I drive...

anyway, while they had the car on teh lift the mechanic pointed out what he said was a coolant leak at my water pump. He said it looked like it was leaking fluid when it was cold - he said the gasket would expand when hot to fill the leak, but when it cooled off, it would drip.. he said the water pumps go out between 75-100k - some sooner, some later - butt hat he recommended changing it.

He said the ballpark price to repair it at his shop with an OEM Porsche waterpump was about $600.

is this fair/reasonable?

is this something I could do myself? while the car was up on the lift, it didn't look all that hard to get to - but stuff always LOOKS easier than it reallly is.....

he didn't tell me I had to fix it ASAP, but he said when it goes - it will just dump fliud and I could wind up stranded...as the car is not a daily driver - and I don't routinely use it for long trips - being stranded would be a PITA, but it would not be a catastrophe.

what do you all think of this? is his info valid? he wasn't trying to sell me on the repair on teh spot - but he did seem to imply that if it was his car - it was something he wouled take care of and NOT "wait for it to break".

any input is appreciated.