DasMafia, where did you get your No1H? If you bought it new, the rings and a action lock should have come with the rifle from the factory! Any Ruger No1 rings will fit the No1 H. The No1 H usually comes with high rings,so as not to interfere with reloading the rifle, but they come in low,medium, or high!

You want as much eye relief in your scope as you can get, if the rifle is a 458 Win Mag, or 458 LOTT.