I could be wrong here, but I seem to recall reading somewhere that Keith Kearcher has done this.
This "one"....An American job would explain it not being marked.
If you don't read the posts, why do bother to reply to them? To make the reading comprehension easier I have put it in bold/red this time. From the original post in this thread.
Yes, you read that right.
A friend (now deceased) had a wreck of a Purdey hammergun brought back to wonderful condition. One really nice detail was that the the 'smith in England suggested sleaving the barrels with some damascus tubes from another gun.