Currently there are 48 native Wideangle Prime lenses for Canon 5DS R and 24 of these lenses are autofocus (AF) type.
Canon 5DS R doesn't have a sensor based image stabilization system but 4 of these Wideangle Prime lenses features optical image stabilization.
Since Canon 5DS R has environmental sealings (Weather Sealing), you may like to couple your camera with one of these 12 Wideangle Prime lenses with Weather Sealings.