If you're a skinflint penny pinching cheapskate like me, then put it on, drive it, and see if you can notice the vibration. Chances are it'll be fine.
If it's really out of balance, you might try what I used to do with my Alfa GTV6: put a screw-type hose clamp around the driveshaft opposite the dent and test drive it. If the vibration's worse, move the clamp 90° around. If that makes it better, move it 45° more and test it again, etc. Keep splitting the difference until you get the smoothest rotation. If there's still a slight vibration, add a second clamp and repeat. If you're patient and have more spare time than money, you can get the balance surprisingly close.