After reading this thread I went over my paperwork in more detail.
My origami seems to match with the example at the Nihontocraft website and the OPs photo.
What is the stamp with the board of education number? Shown in the upper right corner reverse side of the OPs example?
My paperwork is also blank on the back.
My katana and the photo on the paperwork shows 継廣、however the actual paperwork is 継広 in calligraphy. Is this an error or did the person writing the calligraphy get lazy, or is the writing computerized and it is a spell check error. 廣 And 広 are pronounced “hiro” and are alternates to each other.
thanks for any input.