If the belt breaks you shouldn't experience any additional problems other than a tow bill. Do you like sitting on the side of the road waiting for help?
T-belts are affected by oil soaking in from leaking seals, dirt, people racing the engine, yadda, yadda, yadda.
The water pump is a good idea if you're paying someone else to do the work. Reasoning: you get to pay all that labor all over again when it goes bad. It could last another 60k or it could last another week. Who knows? Your gamble.
Try replacing the seal yourself, at the worst you'll lose a couple bucks and fifteen minutes of your time.