Hello Dave,
Did it go out of your ownership some 3 years ago?
It seems to be doing a relatively high annual mileage since it left you, and although I share your wish to reunite the key and car, it will prove to be an almost impossible task, so I think you just as well now junk it ( some 3 years on-?) unless, by chance, someone may recognise the number operating in their locality.
Always worth a try on here though for a couple of weeks.
Kind regards,
Gareth.