MDean,
I would have liked to send you a map showing the 2 properties, Cockburys and Lammerys, but it's not as simple as attaching an image, like on an email!
So, Cockburys is now called Cockleberries, and is on the N side of the Windrush-Sherborne road, almost opposite the village hall. Lammerys is now called Ley Mary Farm, and is on the W side of the same road, just after it heads NW after the village green. They are both shown on the 1978 1:2500 OS map.
The Gloucestershire Archives records that deal with Windrush are mostly from Lord Sherborne's estate, and are listed under D678/1 T1/18. If you search the Gloucestershire Archives website for "Jackson Windrush" you'll get most of the documents that relate to the family.