Hi BgPz, it's really hard to talk about the authenticity of Japanese classics (Dragon and Cherry Blossoms issues), especially when it does not bear any apparent "signs" of the forgery (such as "San-Ko" or "Mi-Hon" or "Mo-Zou" inscriptions) and apparently forged, non-existing cancellation (a good example is the notorious "Mo-Zou" Tokyo double circle datestamp).
Looking at your example, it does not have any apparent sign of the forgery, which sounds positive. The detail of the design , including the loops above and below the right and left value inscriptions are correct. The oddly long horizontal stroke of "4", extending towards right, could be found on several positions of the genuine example.
However the rather blunt and heavy mute cancellation (which is totally illegible), together with the rather dark shade of the stamp itself, makes me feel a bit suspicious.
So my present opinion could be best described as "no apparent sign of known forgery", which does not mean that it's genuine though. In order to draw more concrete conclusion, you might have to refer to the "Forgery CD" published by the International Society for Japanese Philately, which contains over 2800 (!) images of the know forgeries.
For your further information, this site below should be an excellent reference for studying classic Japan in terms of spotting any forgery.
https://japanstamps.org/2021/09/15/...h-syllabics/Hope this helps !
- Hironobu