Just take pictures of the sling and get an approximate length. We can make a guess with good pictures. The additional markings you are asking about are essentially irrelevant with regard to the general history and verification of the correctness of your Krag. There have been discussions about the markings, comparisons of many of them but few conclusions.

Others may add to this discussion but the main points I've discussed are most of what's important.

Forgot to ask about the condition of the bore. Very important in determining a good overall value. Krags with poor bores can be excellent shooters but most of us would like to have one with a good, mostly unpitted, bore.