A little outside your specified range but you might consider the Bull Run in Shirley. If you know the Bull Run from years gone by, you might shrug your shoulders and roll your eyes. I would have too. However, they've changed chefs, approach, & philosophy in the last year or two and these days they are quite good.
That said, I haven't ever eaten Thanksgiving there but, given their new direction and commitment to fresh, local food, I'm betting their T Day dinner wouldn't disappoint.
Bull Run Restaurant
RR 2 Box A, Shirley, MA 01464
We decided on Ceres Bistro..they have an afternoon menu that interests mom..it's a pretty spot. Sonoma and Harrington Farm are closed. Via and all as well...it's all good so long as no one has to cook and clean. We have been dining out for T Giving since Dad died. Last year we were in Anguilla...talk about a great turkey dinner...Organic from a farm in Oregon of all places...