I chose a Leupold VX-2 3-9x33 for rimfire, with Adjustable Objective. You may prefer more or less magnification, but I think you will want adjustable parallax capability.
You may hear some say that "if you can't see it, you can't hit it". Not always the case - quite possible to shoot very tight groups with a target that is matched up to shape of your reticle, to give you a solidly repeatable sight picture. It is quite doable to shoot sub one-inch groups with 2 1/2 or 3 power scopes. Some target shooters do it with double aperture "iron" sights.