hello,  I am new to this forum and also new to Krags.  I just bought a Model 1898 and it has a 22" barrel with a front sight that looks exactly like yours.  I know that mine was sporterized and I assume the barrel was cut down to 22".  I purchased a front barrel band with bayonet lug to try to restore it as close to original as possible and the diameter of the barrel is greater than the barrel band which confirms that the barrel was cut down because it makes sense that with the taper of the barrel, it would be a greater diameter 8" farther back from the muzzle.
Could you measure the diameter of your barrel at the muzzle and compare to what the diameter of a 30" barrel is at the muzzle.  This might confirm that you have a cut down rifle barrel , not a carbine barrel.
Ron