I never heard about A-Bolt bases fitting Tikkas. I'm not saying it's right or wrong - just that I never heard of it.
As for rings, like I said - go with the Warnes, especially with a 7mag. And don't worry about them not having bases. The Warne rings attach to the receiver and are VERY STRONG. In fact, there is a small round key at the end of the front ring that prevents the scope rings from moving - smart idea.
The only thing is this - I use the Warne Silver rings on my Tikkas because they are Stainless. I know that Warne has their Maxima rings available in Matte black, but I don't know if they have it available in glossy black (cause you need them on the Deluxe).
I'm gonna call Warne tomorrow and find out - especially since I just bought the same gun and am similarly looking for gloss rings.
Zachary