[Hitch]

Originally Posted by Tex2002ans

Yes. Especially see my + Hitch's many posts over the years. See my posts in:

Help ;with Kindle Page Numbers (Use the search terms recommended in this post to find all "Real Page Number" discussions.)
Fractional Page Numbering
Real Page Numbers for Reflowable Kindles

I even wrote a post discussing "density of pages" too!

Post #67 of "Fractional Page Numbering"

Those threads link further to nearly everything about RPNs (Real Page Numbers) and various word/page/byte-count schemes.

Bless you, my son.

Do they base it off the internal EPUB Metadata (dc:source)?

Or I assume when Amazon merges Print/Ebook versions in their store, RPNs are something you inform them of and they'll enable it in the backend (at their discretion)?

You do as we've discussed--add the ids based on page numbers, to match the print edition; create a page list, and alert Amazon and in their infinite wisdom and sole discretion, yes, they'll enable it. :-)

Hitch