There are lots of good scopes out there. The Nikon mentioned is a good choice. Another one I'd recommend is a Sightron SII. Others are Burris Fullfield II and Bushnell Elite 3200. Compare features such as eye relief, weight, exit pupil etc. A 3-9 X 40 is a good standard. Even a 2.5-8 X 36 (or similar) would look good on that Tikka. Good luck.