Very hard to tell from that picture, need a close shot from the top on the rear sight to tell you for sure, and a closer shot on the front sight.

If the front sight is a King it will be stamped King on one side or the other.

The rear sight from that shot does look like a factory sight, but if it has grooves along the top of it you may have a king rear sight, which looked very much like the factory sight. The rear blade could also theoretically be King, which was made to fit into a factory rear sight. If it has a white outline it's likely to be a King.