I used Warne 7.3 rimfire rings on mine. Some people don't like it how the top section of the ring wraps more than half way around.
Tikka has a 11mm dovetail. The Warne's have clamps that can fit 11mm and 3/8 inch dovetails.
Burris makes some nice rimfire rings that can also fit both 11mm and 3/8 inch dovetail.