This is the best reference book on Japanese cash coins ever published. Although it has been over 100 years since its publication, nothing comes even close to it, not even the works written in Japanese. Most Japanese books are attribution-guide-type works with little or no help in attribution or explanation. They would attach nicknames to varieties, and it is up to the collectors to decipher what all those terms mean. The problem is that every author seems to come up with different nicknames for those varieties. The author, Suzuki, would call a certain variety CR21, while another author, Honda, would call it BM87. Still, Mr. Kawasaki calls it NN44.
Some collectors say that Showa Senpu is the best, which is a multi-volume work on cash coins. I concur that this book contains the best rubbings of cash coins. However, I do not do anything with Annamese, Chinese, and the like. So, three out of four volumes are useless to me. Nowadays, this book is impossible to find anyways. Furthermore, it is just a book with rubbbings. I bought a set about 25 years ago, sold the three "useless to me volumes" and kept the Japanese volume. I should have it, but I cannot find it.
However, Munro's book is very readable. This is a tough book to put down once you get into it. I just cannot imagine a collector of Japanese cash coins not owning this book. Reprinting it crossed my mind. But I know darn well that most coin collectors do not invest in reference books. They would not hesitate to spend a few hundred dollars on one coin. But, boy oh boy, they would have to sleep over on a decision to spend the same amount on books. Sleep they do. When they get up, they still keep sleeping. But their collection contains a rogue of misattributed and, often, many reproductions.
When I was a kid, reading Dave Bowers' books on coins, and I enjoyed all of them as they are very readable, he often quotes two phrases: "If you do not know your coins, know your dealers." And, "There is no Santa Claus in numismatics." I believe the latter is by Feldman. It was true then, and it is true today. BUT, it is much more complex today. Knowing your dealers is good for starters. Since it is your money, why not trust in your knowledge of coins. If you think you can gain that knowledge without owning the proper reference works, you are not being honest to yourself.
Jacobs and Vermuele's work is not on my recommendation list. In the early 50s, it may have worked for some. JNDA catalog, which is an annual price guide similar to our "RedBook," is OK. Every year they try to come up with something new to entice the buyers. For the most part, the pricing of coins is quite out of proportion. You MUST check Yahoo Auction Japan. This is where the market is made for Japanese coins. You need to install Japanese IME and know how to search the site. So, this is only for the advanced. If you have a command of Japanese language, upon request I can guide you thru.
Ebay got its butt kicked in Japan by Yahoo Japan. Although eBay has many international sites, it no longer has one in Japan. Yahoo auction in Japan is thriving. But because of cultural differences, the sellers there do not ship overseas. In fact, even making a payment is VERY difficult. That is,even if you were able to register on Yahoo auction. Ebay totally mismanaged one of the largest buying and selling biz, which is Japan. However, many improvements on today's eBay are based on Yahoo Japan auction, which is good.
In other words, buy the book before the coin. Get a copy of Munro's Coins of Japan. The original edition is a bit costly but smells great. The reprint is still quite reasonable.