Hi Martj,
Welcome to Rootschat!
I would suggest two things, firstly try writing to the Renishaw Estate and asking them what information they can offer you - worth a shot, if you haven't already tried that.
You could also try a visit to Chesterfield Library, and look at their old maps that they have in the local history section, if there have been any changes to the building that will show up on a map - pick their brains, they may well have Balborough local history info too.
Is there a Barlborough local history group, or an old folks club? Always worth a try for old local information!
Good luck,
Copperbeech5