Door mirror internal grommet fix

Most of us have needed 1 or 2 of these in our time ... & flea bay have them at a prohibitive 4,5 ...£6 each or even a pair.
Try these , designed for furniture in the main, these are £1.50 or so for 20 ... most smaller diy stores stock these. ..so even if a couple drop out or blow away at that money its no big deal a little glue or mastic should sort that though......see photo

This got me thinking as the missing grommets has always annoyed me. The hole is 1/2” ( British car after all), what could I use to punch 1/2” plugs? Answer is 15mm copper pipe filed to have a sharp edge. I’ve punched the plugs out of the centre of 1” grommets, but any other suitable plastic item could be used.

That's good ..snugger fit than the ones I used .