Are you familiar with
calibre? If the ebook doesn't have DRM, then you can use calibre to convert it to mobi, which will work on your kindle. (If it does have DRM, then there are ways to get around that.)
That's provided you are willing to install software that you may end up not using all that much. And provided the ebook is in a format calibre can handle.
Freedom is merely privilege extended, unless enjoyed by one and all. — Billy Bragg