You can just buy a Nex with the LA-EA2 SLT adapter.
You’ll get acces to all A-mount lenses with phase detection AF.
In fact, I don’t understand why anybody would buy the A77 ??
The Nex-7 has all the same features in a smaller-lighter package, + it can also use almost every lenses ever produced, and get rid of the translucent mirror for an extra 1/2stop of light and increased sharpness.