I've got the 200mW 5.8GHz Rx/Tx set from Hobbyking and a 7" screen from BangGood (or GoodLuckBuy, I can't remember).
I'm using a little video camera I got ages ago, but am planning to eventually use my GoPro.
It was about $120 for the whole setup and is tolerable. I've got some cloverleaf antennas on order.