Ayuh,.... Replace it...
You may or may not be able to find a switch exactly like that.
You will need to turn off the power, unscrew that switch from the wall, and measure the space and the spacing between the screw holes. Then find a switch that fits.
It is possible you will end up with a switch of a different style, for example with a toggle that flips up for on and down for off.
A few folks, I would guess those who built model ships and planes in an earlier life, may be able to dissect that switch and repair it.
I thought so. Check with a local hardware store or supply house for a replacement switch. It should be an easy task to remove and replace it.I am in Australia.