I have a feeling that the MRO have plans from the Pendarves Estate. I recall seeing some of those before (photos of).
The sett boundaries/maps are interesting, but I can't really see them being of commercial interest to anyone, or anyone wanting to put them on their wall.
I bet there is some gold in there, but I reckon it will probably not be too inspiring price wise. As said before, it's really something which should go to the CRO.