Broken Seat Belt
 

My seat belt broke today, before I left my house and got pulled over none the less. It's from an 89. The metal piece that holds the belt inside (this part) http://www.brake.org.uk/resources/im...lt%20large.jpg just fell out. I can put it back in, but it just falls out once it moves. There is a black thing that is on the metal bar on the passenger seat belt, but I can't find it anywhere.

Anyone have any ideas on how to fix this? I was thinking duct tape and hot glue, but I don't know if I would trust my life with that..