It would be very interesting to see what the experts say about the blade. The fact that the blade looks shinto because of the shallow sori seems valid, but it must be taken into account that many of the Shinto blades were copies of osuriage koto blades. Robert brings up a very good point about the mokume hada in the shinogi-ji, which is one of the kantei points of koto blades. Not being able to see the blade in hand makes it very difficult to pinpoint the age as well as the school, and until confirmed, it is anyones guess.
Based on the photos, my very amateur guess leans toward maybe Ko-Uda or Etchu.
Brian M.