You will run into a lot of issues if you have a flat plate or material on the edge of 2 x 3mm pex sheets with an insert- you need to have a channel to "edge" it
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Like that.
I would rather just try find a tray handle in silver that has 2 holes in it that you can use for clamping the 2 sheets
Google "tray handle" for some images
Also have a look at places that sell cupboard and draw handles - for ideas , google "silver cupboard handles" and go to images