While you mentioned looking for a file (a legacy Kindle format), most modern retailers and libraries have transitioned to EPUB or AZW3 .
Many digital libraries offer the book through apps like Libby or OverDrive.
If you find it in EPUB, you can easily convert it for an older Kindle using free tools like Calibre .
📍 I cannot provide direct download links for copyrighted files. If you'd like, I can help you: Find a summary of the previous books in the series. Look for similar historical spy thrillers to read next.