2000 Heritage Softail stock seat ??

[twincamzz]

My son recently acquired a 2000 Heritage Softail with the stock seat. On the bottom of the seat pan on left & right there are 2  "spring loaded bolts" that are used to secure the sides of the seat to the motorcycle.  They screw into these hollow pieces  that thread into the frame on both sides. One of the hollow pieces that thread into the frame is missing. I have looked at the parts diagram at Ronnie's HD  & cannot find them shown in seat or frame diagrams or even find a part number .
I realize that if the seat is used with the passenger section installed then the rear tab will hold the seat on just fine along with the tab at front of the seat. However if just the solo rider section of the seat is installed then the  mounting bolts on side of seat are required to securely hold the seat in place.
I apologize for the lousy description but really hoping somebody here will understand what part I am looking for & be able to point me in the right direction. I need one of the hollow pieces that thread into frame to accept the "spring loaded bolt" on the side of the seat.
I am attaching a picture of the bottom of the seat for reference.
Thanks in advance for the help !

[rigidthumper]

52720-00A

[twincamzz]

THANK YOU  !!