You can also try a free beta version. Two years ago I applied to the Unreal Dev Grants and promised to make the system free. So I will leave the ability to use free version. But in order to continue the development of the system I need to have an income. I hope everybody understand this.
Beta is available for UE 4.14, 4.15, 4.16, 4.17 engine versions for windows only.
Download Eyes Rig Script For Maya