Hello Jamie, I've never seen the chart. My knowledge comes from corresponding, some thirty years ago with people who had access to the chart or to John D. Primrose's notes (i.e., his son). As I could find no reference to the chart on the internet, until I found this site a few days ago, I put a few notes of my own together, and posted them on a blog on surnames - http://jemmyhope.wordpress.com/2013/01/25/156/ I'm not sure that this will be of any help. An enquiry at the Scottish Genealogy Society might produce some advice.
Lord Rosebery's Primrose tree is a roll of blueprint with a diameter of about 6 inches. It is therefore impossible to file with books.
I last saw it about 50 years when my Father borrowed it from the Scots Ancestry Council in Melville Street Edinburgh. It unrolled to about 7 metres!
When the SAC shutdown about 1970 it was offered to either the Scottish Genealogy Society, or to the National Archives,Princes St. Edinburgh, or to the National Libraryof Scotland, George IV Bridge Edinburgh.
As my Father corresponded with its compiler, John Primrose in Coventry, and offered him several amendments, it is possible that John Primrose's patron, Lord Rosebery at Dalmeny House, Midlothian has these letters and amendments,. It is also very probable that Lord Primrose has a copy of the blueprint.