Mmmm ...
Agusta suggests your local BMW car or motorcycle shop, but try getting a dealer to do anything without a VIN number is impossible.
Its a problem isn't it?
Might I suggest talking to a locksmith .... if necessary taking him/her to see the aircraft and you proving to them that the key is in fact for an aircraft then threatening them with a case of beer for a job well done if they would cut you some spares ... all they need is to be reassured that you are authorised to have those keys and that they will not be liable for any car theft conspiracy charges in the future.
Good luck