At Plymouth, Massachusetts is a replica of the original Plimoth Plantation, complete with actors who, depending on your point of view, amusingly or annoyingly, respond to you only as a Pilgrim of the 17th century would respond.
http://photos.igougo.com/photos/journal/pref/Pa220011(2)_prefRes.jpg
The actors are probably plumper than the Pilgrims and Native Americans were in 1620, when the climate was harsher and food was harder to come by and prepare. Otherwise, they are very authentic.
Years ago, you could have a Thanksgiving dinner, on Thanksgiving Day, cooked as the Pilgrims would cook it, including turkey roasted over a fire. Then, it turned into a Victorian Thanksgiving. Now, they are serving something called "America's Thanksgiving Dinner" or some such.
If you want the fancy (and pricey) meal on Thanksgiving Day, you pretty much have to reserve by around June 1, when they first start taking reservations. However, the same meal is also served the next day and, checking the website, I see that they still have slots for next Friday, if anyone is interested.
http://www.plimoth.org/dining-functions/thanksgiving-dining-special-events/thanksgiving-dining#ATDThere is a very reasonable ($20 this year) Thanksgiving buffet served in the courtyard on Thanksgiving Day, too. That is first come, first served--no reservations accepted. So, if you haven't bought your turkey yet.......
I have been to Plimoth Plantation, but I have never been for the Thanksgiving meal.