Sweet Bruce. That is an uncommon 'English Best' Turkish variant called 'Rosen', with a weld line down the middle of each scroll.
I added a couple of your pics, with an attribution, at the bottom here
http://www.picturetrail.com/sfx/album/view/18059733
Rosa damascena
'13' means the bore at proof was .710-.718, '13/1' = .719-.728, and '12' .729.
What is the bore now?