I don't think that 2133 with work, but 1866 will most likely work without any major issues. That being said, I think that it is best for you to stick with the 1600MHz ram, as using a different RAM speed can cause intermittent issues. In addition, using a faster RAM will not result in any performance improvements, as it's speed will be lowered to the speed of your laptops FSB, which is set at 1600MHz.
The maximum ram limit is 16GB, and either way, that is the most that you will be able to install as there aren't any RAM sticks that are larger the 8GB in the format that your laptop takes.