The "Leica nipple" is also of use on Nikon Fs and others, it's for older cameras and adapts them to use a standard cable. If that is what you need, that is. Is there a thread around the base of the shutter button, say a bit less than 3/8" in diameter? Also, is there a "T" setting on the shutter?
Edit - If there is no "T" setting, you'll need a locking cable.