True about "being screwed" if it breaks.
If you take a piece of 1/8" x 1" thick aluminum "bar stock", you can drill it a thread it with a tap.
Pop rivet it back on like your broken piece is.
That will be more reliable for you and almost as simple of a solution.
I did that on the trunk liner retainers rather than have the same issue occasionally like you have had happen.
That I did so I could switch to a retaining bolt (1/4" stainless button head screws) rather then the dzus fasteners.
It is almost the same plate you would be making for your armrest except for the thread type and size you pick.
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