It's not a part I could find as it's part of the door armrest assembly.
If so you could try to reconstruct it using a quick setting epoxy for plastics then following up with a heavier duty epoxy.
Rough the surface then apply across all the sections like peanut butter and almost as thick. Try to get all sides so it's evenly distributed.
Once dry it should hold.
Most of the Part sites don't list a lot of the clips and fasteners that attach things anymore. You have to go to the dealer to find out what the part number is then you may be able to find it cheaper if the dealer wants too much..
You need more posts to add a picture so hard to tell what your talking about..
If you take it off you maybe be able to find a match here..