if you use the map for airports in the market place, if you have bought from market place it will have a tick on it or of its a hand crafted airport then it shows what pack it comes from and usually has a tick too.
ive only bought once then realised i also had the hand crafted version . also remember if you buy a third party airport and its to replace a hand crafted one for example Heathrow then you need to delete the hand crafted one in content manager