About Wicked Wargames, provided by the creator on YouTube:
Would you like to buy a copy of The Momentous Issue of War? You have two options:
1. To buy the book: write to me at wickedwargames@gmail.com
The price is £10 + postage. We can figure it out via PayPal or something else if you have another solution.
2. To buy the PDF, go here:
https://www.wargamevault.com/product/399132/The-Momentous-Issue-of-War?term=the+momentous+iss
The price is $12.13 (as of 20th of October 2023).
Full disclosure:
This game was made by two friends in a business partnership. However, we are no longer friends. I sell the books and he sells the PDFs. For you, this means that you're not contacting the Wicked Wargames partnership (which no longer exists), but one of the people who use to be a part of it. Does it matter in terms of the product you'll get? Not in terms of the book, and I assume not in terms of the PDF (we no longer speak, so I can't really comment on the PDF).