It has what are likely Silver inlay bands on the bbl's at the breech. As usual they are tarnished down so hard to see at a quick glance. LH side on pic4 shows how they can hide when tarnished.
Perhaps the makers/retailers name is also inlayed in silver on the rib as well.
I like it as well. Imagine what it cost to have one made or upgraded on an existing SxS these days.
No pic of the bores unless I missed it in the glance thru the pics.
The gauge is not mentioned which is kind of odd,
The write up sounds AI like to me. They could have offered more info on bore & chamber condition and specs.
It does however mention 'silver fittings' on the gun. So maybe a silver inlayed rib marking as well.
Probably some markings on at least the action flats, ser# and maybe some proof marks.
There is a ser# on the BP, so I'd expect it to appear other places.