It is likely that the right bore (and possibly both if the gun is Continental) has been honed, making it even more critical that someone with the interest, equipment and expertise to do so (like Bro. Dennis) has evaluated the barrels; NOT the seller.
If the report does not include MWT at the end of the chambers and the forcing cones (near out eyes) and every inch out to 16" - 18" (near our forward hand), it is inadequate.
I believe Osthaus meant .045" 9" from the breech.
More here
https://docs.google.com/document/d/1ZIo0y746UsSRZIgRuuxwAbZjSBHitO_EanvwLYc-kGA/edit

https://sites.google.com/a/damascusknowledge.com/www/home