I'll cast my vote for a 260/6.5 Creed/6.5 Swede. Tikka or RAR Compact.

"Whatever you do, be sure that she picks it out. You want her to be happy with it, and for it to feel right in her hands."

Now I have a problem!!!!, I told her that I was going to get her a new rifle for our 40th anniversary and she looked at me and said, "I like my 30-06. I had it for almost 40 years. I shot it 25 times and have 21 whitetail, 2 mule deer and 2 antelope, all on the ground, all with one shot. Why would I want a new one?"

Her rifle is a long story. It is a Springfield 1903 Sporterized 30-06. When I was in high school, the ROTC program was in a portable building. They had 30 original and fully functional Springfield 1903....it was a different world then. The building caught fire and everything burned up. I bought 2 of what was left of the riles for $5 each. I saved up my money, (this was in 1969) and had them both Sporterized. Cost me a total of $100. Then I saved up some more money from cutting the lawns in my neighborhood during the summer and bought two Weaver 4 power scopes. When she came along, I had the stock cut down a little, I did not have it fitted to her, I did not know you did stuff like that. Anyway, that is the rifle that she has used all her life and she has never even shot another one. Only change is that two years ago, I took the 4 power off and put a 6 power on. I too had only shot my rifle until two years ago, when it began hurting my shoulder and so I decided that I needed a Weatherby 270 because all my life I have wanted one. I bought it on my 65 birthday.
I love my wife very much, so I'm still going to buy her a new rifle and most likely it will sit in the closet while she uses her old Springfield. But maybe someday she will try it....Women, if it was a few new pair of shoes I was talking about, she must have 50 pair now and would jump up and down at the thought of some new ones. So, maybe we will get both.

Since she likes her rifle so much, and she probably won't hunt with the new one you get her, why not get her a really nice .22? She could shoot it for practice and plinking. Henry and Browning make levers with beautiful wood. Or search around for a really nice bolt action with good wood.

I think a 6.5 Creedmoor would be outstanding for her but I'm a little partial, that being said 6.5x55 Swede, 7-08, 25-06, will also work great!

You sure that woman is 70? She doesn't look a day over 55