If I remember, I can take a few pictures tonight. This is a good question, where is a source for carpet and door fasteners? What does the pro use?
I found this page and the prices are very much unreasonable. I have seen a good number of these exact fasteners on the Aveo.
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I think you just need to pull the door and see what you got. Maybe this should become a sticky thread for the audio/interior section is a list of fasteners and sources with pictures.
Robot Check