[dave3d]

It is known as a Dzus fastener. They are a pain in the butt and never work.
Not listed as a separate L/R part but can be bought from fastener suppliers if you find the right size. There may be a minimum order though.

 

[dave3d]

https://www.southco.com/en-us/81-82-85

 

[dave3d]

There is also a plastic retaining washer that stops the thing falling out in the first place. You can see it in your pic.
I don't know where you get those, but you could probably make one.

 

[dave3d]

So how many did you have to buy in the end? What was the minimum order?