Ok, I know it's not exactly a double, but it isn't really in the spirit of the single shot section and is an early shotgun/fowler and of the highest grade, So I think it will still be appreciated and hopefully I can get some help. (If not then by all means move it to the single shot section)

I'm trying to find more pics of this gun.

It's supposed to have been made for the king of Portugal in about 1815. Has anyone else seen pics of this gun? I've searched everywhere and have found nada.