Jean et al -
Thank you, I am glad to be here and always glad to talk swords. Kantei from photos is always a dicey thing, even with a sword in hand I am wrong 9 times out of 10. Based on what I see in the pictures, there is no color change in the nakago nor any difference in the look of the yasuri mei to indicate machi-okuri. The mekugi-ana appear new, they appear drilled and the placement is odd for an older piece. There appears to be a distinct lack of nie in the close ups of the boshi and the hamon at least that is how it looks to my eye. The jigane looks to be mujihada except in that one picture, but they are just pictures.
The torokusho may give us the answer, it might also just say "katana, Mumei", in either case I am curious to know more about the piece and I am grateful for the opportunity...
-tom