Handmade Small Booklet For Japanese Coins

Very interesting and seemingly unique.
Hopefully, someone here can shed some light on the coins!

That is very interesting. I wonder how to authenticate these supposed Samurai coins

The coins are fairly standard mid-1860s Japanese proto-coins. They date from the time when Japan was rapidly industrializing and still trying to figure out exactly which bits of Western culture to fully adopt, and which bits could be given a Japanese interpretation. In this case, we see both Western and Japanese aspects: "coins" that were mass-produced in the Western fashion by machine striking but did not need to be round, with designs instead resembling traditional Japanese paper money.

The larger one is an "ichibu gin" or "1 bu silver". Wikipedia. Numista.

The smaller one is a "Manen Ni Shuban" or "Manen Era 2 shu coin". It is made from very debased gold (about 23% gold and 77% silver), so that it might more properly be called "electrum". Wikipedia. Numista.

The coins are not expensive, though probably more so these days with the high bullion prices. I would dispute the book-writer's premise that they are uncirculated and in "pristine condition". These coins were not in circulation for very long, but these examples almost certainly saw circulation during that brief window.

I suspect the book may be a "tourist item", with genuine coins but packaged up in a way to attract Western tourists.

This is my personal opinion. It would be difficult to believe that this is made in Japan based on the age and text font. The font alone makes it likely to be manufactured in the US, however the odd grammar structure would suggest that it could have been made by Japanese community in the US. As California is home to one of the largest Japanese communities - thus my deduction. I wouldn't be surprised that this could have been a tourist package thing back in 1960s.