Hello Robert,
the staple like iron retainer I've never seen before but I am nearle sure that this dagger scabbard :
http://www.vikingsword.com/vb/showth...ilippine+knife from my collection has had once a very similar belt hook also when it is now carved away maybe because it was broken at one point of it's history. It's not good to seen on my pictures but when you hold it in your hands you would most probable agree that it was of a similar construction.
But it's still a guess.
Regards,
Detlef