FreeStar
As far as I know, Windows only displays the refresh rates that the monitor or TV reports via EDID - a special table of supported modes. If your monitor does not report support for this refresh rate, then it is not on the list.
But you can set a custom refresh rate in the Nvidia Control Panel (there should be a "Customize" button in the "Change Resolution" panel), but do that at your own risk! I don't think it makes sense, since if your monitor or TV doesn't support certain refresh rates, you'll either trigger a frame interpolator or just get a black screen.
P.S. Your monitor or TV could still cause eye strain because of things like PWM, dithering, pixel inversion, and so on - not just because of the wrong refresh rate.
P.P.S. At one time, I gave up on Nvidia because even the 1650 - which many people praise - doesn't work for me. But that's just how my eyes "work"; you might have a completely different experience.