I'm only familiar with Australian copyright, so some of this may not apply.
Copyright can exist on a document regardless of whether there is any copyright notice or not, and although as Steven says, facts can't be copyrighted, how those facts are put together can be, particularly if you are planning to scan pages and add those images to profiles on Wikitree.
My advice would be to see if you can contact whoever published the document in 1984 and get their permission. The other alternative is to just use the document as a source and not post any images.