There is really not much information to dig up on this brand.
Old bottles of Ballantrae with the same label image as this jug is stated bottled by Boddingtons Brewery Manchester which was bought by Anheuser-Busch in 2000.
IB bottler A.D. Rattray located on the west coast of the Lowlands near the village of Ballantrae occationally use the name on undisclosed malts.