Be careful about how big you go. There is a general range that's ideal for each tv size. To big a tv for how far you are sitting from it will actually hurt the picture quality. I bought a 32" for the bedroom and ended up taking it back and getting a smaller tv for this exact reason.
So measure the opening that the TV needs to fit in and see what your hypothetical maximum is. Here is some information regarding seating distance from tv's for you.
Finding the Right Distance for Your TV
How far to sit from your TV depends on both its size and the type of screen you have. If your TV is a traditional 1080p HDTV unit, the TV size distance ratio is between around 1.5 and 2.5 times the diagonal width of the screen. This means that if you have:
A 40’’ TV– You should sit between 5 and 8.5 feet away from the screen.
A 43’’ TV– You should sit between 5.5 and 9 feet away from the screen.
A 50’’ TV– You should sit between 6.5 and 10.5 feet away from the screen.
A 55’’ TV– You should sit between 7 and 11.5 feet away from the screen.
A 60’’ TV– You should sit between 7.5 and 12.5 feet away from the screen.
A 65’’ TV– You should sit between 8 and 13.5 feet away from the screen.
A 70’’ TV– You should sit between 9 and 14.5 feet away from the screen.
A 75’’ TV– You should sit between 9.5 and 15.5 feet away from the screen.
An 80’’ TV– You should sit between 10 and 16.5 feet away from the screen.
An 85’’ TV– You should sit between 10.5 and 17.5 feet away from the screen.
Compared to 1080p HDTVs, you can watch the more advanced 4K ULTRA HD TVs from a smaller distance without straining your eyes or seeing pixels. The ideal TV viewing distance 4K Ultra HD TVs is between about 1 and 1.5 times the diagonal width of the screen, which works out to the following distances:
A 40’’ TV– You should sit between 3.5 and 5 feet away from the screen.
A 43’’ TV– You should sit between 3.5 and 5.5 feet away from the screen.
A 50’’ TV– You should sit between 4 and 6.5 feet away from the screen.
A 55’’ TV– You should sit between 4.5 and 7 feet away from the screen.
A 60’’ TV– You should sit between 5 and 7.5 feet away from the screen.
A 65’’ TV– You should sit between 5.5 and 8 feet away from the screen.
A 70’’ TV– You should sit between 6 and 9 feet away from the screen.
A 75’’ TV– You should sit between 6.5 and 9.5 feet away from the screen.
An 80’’ TV– You should sit between 6.5 and 10 feet away from the screen.
An 85’’ TV– You should sit between 7 and 10.5 feet away from the screen.
https://www.avu.ca/video/perfecting-...0the%20screen.