61 Lancer horn center

button....the horn ring is intact and working well.....I am missing what I would think to be a combination ring with the three spring loaded tangs...but this is only speculation on design as I have nothing to go by...no pics, nothing in the manual shows this either.
I'll go and look at mine and get some photos but it may be tomorrow, got to ship off my radiator to be re cored today
Larry