Bronko is right, the Tikka action has built-in bases, so you're looking for a set of rings that are a direct fit.
Warne makes a set of medium and high rings in 1" specially made for Tikka:
http://opticscamp.com/warne-scope-ri...edium-1tm.html
http://opticscamp.com/warne-scope-ri...-high-2tm.html