No problem,
JS.
In UK, US and AUS, that I know of, you can effectively "restore" something around the maker's plate and have it certified as the original aircraft.
Just two examples of that would be that Spitfire, the remains of which were recovered from a French beach, (it had been sitting in the intertidal zone since 1940),
then 'restored' in the UK and which, I hear, has recently changed hands for some five million.
How much of that (engine and airframe) is original, do you think? The maker's plate is original, though.
The second is an Fw190-A5, some remains of which were recovered from under a railway yard in Rheims and, over a number of years, it was 'restored' in the US
and certified as a Focke-Wulf Fw190, rather than a Flugwerk FW190 - which some say it really is .. except for the original's maker's plate, of course.
That one is currently flying in Oz.
I could go on, but you get the picture.