Another 97 Ram Van issue

I have a 97 Ram 3500 Van 15 passenger with the big sliding side door. When you close the door it latches and then you should be able to pull the handle up to lock it in all the way. I went to shut the door and it won't latch now. I think that some sort of pin or clamp broke that makes the door lock in securely. Can anyone point me in the rigth direction on how to fix this or what parts I might need.

Thanks,
Jamie