We planned for that a long time ago. Which is why all the documentation links in the admin panel and in features can be changed to your local copy.
ex. doc.tiki.org/Blogs becomes tikidocs.lan/Blogs
However, I don't remember this happening a single time. People just use the online version to have latest version.
We even had an automatic dump of doc.tiki.org which was stripped of data like usernames, etc. but I think it disappeared because no one was using... Maybe it's time to bring this back, but you would get all pages...
How many pages do you have in mind?
If it's just a few dozen, simplest is just to copy-paste source to your local instance.
We could also make a profile (profiles.tiki.org) which would contain some of the most-used info.
We could give you a dump of doc.tiki.org but it's huge!
Ideally, we could have some sort of shopping cart for pages where you pick & choose what you need, export to XML and re-import back.