The date of the used text is that of the speech, therefore the date it was written should be used, if available, and added too the information that it has been compiled in a book with a more recent date, because if it appears in this book, it may also appear in another, therefore the date would change depending on the compilation, but not it doesn't what changes is the date of the compilation, but not that of the text. So I would state the original date and offer the information of the more recent book where it may be found.
