Remove shaver socket for a PIR

I have a shaver socket that never gets used, the cable then goes into a over sink light fitting, so i was thinking that id get much more use if i could take out the shaver socket and replace with a PIR, main reason is for when kids go toilet in the night as they cannot reach that light and i dont want main light on as it will turn on extractor (ie i dont fancy turning off the isolator ever night)

Is there a PIR that would fit on a 2 gang box?

 

Thanks for the links, much appreciated