What grade is it?
 

Can it be told from these photos what grade this Parker is?

looks like a small-bore DH also known as a Grade 3

Thanks, kinda what I was thinking.

Water table markings?

Don't have access to the gun, just some photos.

Do these photos of it's stock look like what one would would expect an a D/3 grade?

Not the correct stock details. Check the home page of this site for pictures of the different grades.

If these are in black and white from the source and it’s not someone you know personally I would steer clear. It takes extra effort to make photos be black and white and less revealing. Food for thought.

Leon, The cut barrels and more than likely honed with cylinder/cylinder chokes, the refinish on the forend, barrel reblue, wrong and or buggered screws everywhere, top lever left of center, and the bluing of the entire frame would lead anyone to believe that DHE 16 has been rode hard and put away wet. Good deals on bad guns........

Yup. Source is trustworthy. Maybe nostalgia, as only B & W was available when the old girl was made some 100+ years ago.