Cobalt blue flow Willow pattern salt shaker, Made In Japan

So here is another out of the bin random thing. It came with an antique shop price tag which seemed high value for this little salt shaker. Measures 2 3/4", appears to be cobalt blue flow Willow Pattern, although I don't see signs of transferware, I would guess that it is because of what looks like the seam in the collar decor, stamped Made In Japan on the base. My guess is actually pre-war Japan, which is when a lot of blue flow Willow was produced and exported. What do you all think? Marking this one mystery unsolved for now until I hear a good explanation for why it might be valuable. Thanks for looking and I hope you enjoyed seeing this pretty salt shaker.