New volume/power buttons miss little metal circles

I just swapped the housing on a very scratched iPhone 5 from black to silver. The included volume and power buttons are missing the little circle-shaped metal plates/dots on them, there is just two holes where they should be on the volume buttons and one hole on the power button. On the original buttons there is a little thin metal plate in these holes, which makes them work. The buttons in the iFixit store also miss these as I can tell from the pictures. I tried filling the holes with superglue, but that did not work. Is there a way to remove this little part from the old buttons and install on the new ones?

Thanks :)