It's difficult to find input lag numbers for older sets (yours is 2011, I think) because the Bodnar tester didn't come out until 2013 or so and the other methods (comparing pictures of the screen next to a monitor, etc.) are imprecise and hard to do in a showroom/sales floor. That being said, by looking at similar sets in that age/model on displaylag.com, I'm going to guess that your set is probably in the 35-40ms range which is not too bad.
If you want real numbers you'll need to get a Leo Bodnar tester which is around $100. I've often wondered about the lag on my own SXRD TV from 2006 (and my new receiver, too) but not enough to buy the tester.
As an aside, Displaylag.com really started out as a great resource but has been disappointing lately. Maybe he's just busy with life but he doesn't add many sets these days. One would think you could spend an afternoon at Best Buy and come away with dozens of new entries for the database. Only 16 2016 sets listed and not one OLED. Ah well.