Happen to be sitting on a basket of E34 sport seat parts?

Here's what I need - on the front sliding bolster, on the bottom, there is a plastic guide piece that holds the bolster to the guide rail. Need one. It's riveted to the frame so I'd be happy to work with you on some creative removal plans. As best I can tell, it's not an orderable part.

On the other hand, if anyone knows the part number for this little gizmo, I'd be most appreciative. And no, the one from the E30 sport seats don't work.

Jeff