When I am at a stop and I make a left or right hand turn, I get some vibration in the steering wheel. I am 95% sure that this has nothing to do wit the wheels or tires. I then looked at my power steering reservoir and the top has three notches on it. The manual says it should be between notches two and three. Mine comes up to the top of notch one. So, do I top it off? Also there seems to be a few threads on what type of power steering fluid to use. I am in the US, so certain brands may not be readily available.
Thoughts?

Definitely top it up with the manufacturers recommended fluid and check around the steering system for any possible leaks.

Mobil Dexron 3 is what is specified but any Dexron 3 fluid would work

This is an age-old problem with many people speaking of it. A fluid change sometimes makes it more easily dealt with, sometimes not.
Other people say it's from the E-diff, shaking all the way to the wheel.

The Manual calls for Pentosin CHF 202. Is Dexron 3 the same thing or compatible?

Pentosin doesn’t say Dexron 3 in their specs as it is specifically power steering fluid and not ATF. My 2008 manual says Dexron 3.
I would use the Pentosin 202 (or 11S) which are both synthetics. Pentosin says not to mix with earlier 7 fluid as not compatible.

Given the age of the car, have you had the fluid changed? The reservoir changed? The filter is at the base of the reservoir.

The car is new to me. I am guessing no.

In my particular case, steering wheel “feel” was significantly improved by performing a flush. I went the extra step and replaced the reservoir.
Absolutely stick to the specs for the replacement fluid.
You may be surprised to see just how bad the state of the current fluid is when compared to fresh. I was.

I recommend not flushing it, and simply extracting the fluid with a pump from the reservoir then refill, drive around, and do it a few times.
These are sensitive systems under high pressure, You don't want to disturb any contaminants in the system.

Thanks for the advice Guy and Tarokyama. I will confirm and try a thing or two. If I suck out (Ohh) the reservoir, how much fluid does the reservoir hold?

I don’t recall how much the reservoir holds but estimate about 12 Oz. I used 1 1/2 liters to flush and fill the fluid in my power steering.