Wheel Bearing Issue

I just bought a 2000 Protege ES. I'm thinking it has a bad front passenger wheel bearing based on the noise. It is a thump, thump, thump that is dependent on speed. It is easier to hear in left turns and when you let off the gas. There is a lot of noise at 50mph+. The only symptom that doesn't fit is that I read there is supposed to be a lot of vibration. There is no vibration. The car rides super smooth. There is no pull and it drives straight. I'm trying to decide if the tire is just bad because it was nearly flat when we bought it (it was repaired), but wouldn't that cause a lot of vibration? I'm really stuck where a lot of these problems that could be causing the noise should also be pulling or causing vibration.

Any opinions?

Unless the bearing has a lot of play in addition to being worn (causing noise), then you probably won't feel it.

The tire could have a belt shift (perhaps as a result of that flat) - try moving it to the rear or other side (if non-directional) and see if the noise follows.