Currently there are 23 native Telephoto Prime lenses for Sony A7 and 18 of these lenses are autofocus (AF) type.
Sony A7 doesn't have a sensor based image stabilization system but 7 of these Telephoto Prime lenses features optical image stabilization.
Since Sony A7 has environmental sealings (Weather Sealing), you may like to couple your camera with one of these 17 Telephoto Prime lenses with Weather Sealings.