I've got a couple of passenger side third row seat seat belts. My drivers side has the same issue. There are differing versions of the buckle however. You'll have to show a pic of the male and/or female end as the bottom receivers are joined and you cannot mix and match male sections. In other words all third row seat belts are not the same in the w123- just as not all front row or second row seat belts are the same. The key in used seat belts is to insure that the belt feeds out and retracts smoothly and the unit is not about to fail due to underuse or abuse.