I recently purchased a previously owned 1991 Citori GTI that came with 2 Invector Plus chokes that are longer than extended chokes. I would like to purchase additional Invector Plus chokes that are the same size/type, but am having difficulty finding them. Does anyone know what they are called and where I could buy them? I have attached a picture of one of the chokes that came with the gun along with the shorter "extended" choke I recently purchased.