Nuts and bolts, nuts and bolts, anyone?
I believe the screws (really bolts) are high crown phillips head. They may be the same screws as what's used to mount the jack handle behind the door (5/16"). The top screws take a washer and nut each. The bottom screws use that and lock washers.
Here's nut & bolt that may be right. Be cool if it is, because I just bought the set.