Currently there are 13 native Standard Prime lenses for Pentax K-1 II and 7 of these lenses are autofocus (AF) type.
K-1 Mark II also has a sensor based image stabilization system which means that all of these lenses will be stabilized when used on K-1 Mark II.
Since Pentax K-1 II has environmental sealings (Weather Sealing), you may like to couple your camera with one of these 2 Standard Prime lenses with Weather Sealings.