That listing is rather typical of a U.S. seller or broker regarding a Mannlicher Schönauer as 'one of those funny foreign things'.

The photos do reveal some clues:

The company name was changed from Osterr. Waffenfabr. Ges.-Steyr to Steyr Werke AG in 1926. This receiver was made prior to the change.

The front receiver ring is not marked 'Made in Austria' as it would be if made after 1924, unless made from 1938 - 45 and thus marked 'Made in Germany'.

This rifle was made before 1925. Some or all of the British proof marks are from a later period. If unaltered, it is chambered for 9X56 Mannlicher Schönauer as were all M1905 MS.

The British proofs.

From what the ad shows, it seems to be a nice, unmolested, M1905 save the addition of express sights. The 'uncut' receiver (not modified for scope mounting) is a plus and the original butt plate is still present. Are the cleaning rods included?

The original MS proprietary cartridges, each specific to their model:
M1903 = 6.5X54 .... M1905 = 9X56
M1908 = 8X56 .... M1910 = 9.5X57

2.22?