'olBear' - I am away from home and only have Joe Poyer's Krag book with me. I don't know how good this piece of data is and can't cross-check it.

Per Joe Poyer (page 163): "The Model 1898 rear sight was used on all Model 1898 rifles assembled circa serial #s 217,400 - 253,000."

Information in the Poyer book should be taken with a grain of salt and checked against more reliable sources.

The model 1898/Dickson sight has a lower base than the later model 1902 sight. It was calibrated for the 2,200 fps cartridge which was removed from service around March, 1900. The Dickson sight and higher velocity cartridge were short lived. It was intended the Dickson sight be removed and replaced.

Some 1898 sight parts got into the hands of surplus dealers and were potentially 're-used'.

I've got to come in from the Sun, once in a while, and it drizzled for two hours one day!

FWIW - A correct model 1898 sight is relatively hard to find loose. To a collector a model 1898 rifle sight may be worth about twice the value of a model 1902 rifle sight, in any of its variations.

(With carbine sights, the model 1902 carbine sight is likely rarer than all other carbine models, but, that does not translate into dollars or demand).

On a rifle, when the originality is questionable, a model 1898 rifle sight probably doesn't add much value. (IMHO - $0 to $30).

Other KCA members with access to relevant sources may have better insights.

I believe the 1898 rear sight is incorrect on any Krag rifle as it (the sight) was withdrawn from service never to be used again whils the rifle remained in service.

If I am repeating what others have posted I apologize.