The motor is going to need bearings in all likelihood. Bearings can only get worse and can instill some wobble in the shaft. While some have successfully changed them, I usually swap the motor and seal set. Ignoring it will result in leaks, worn wet end, electrical shorts, or worse.
This was similar to my case where I ignored the issue of the leak/noise for too long. Now the leak caused rust and made the fix much harder if not economically impossible.
So, my recommendation is as soon as you notice a leak from the pump or excessive noise, fix it ASAP!
Trust me, I learned my lesson.