Hi Gerard,
Thanks for the post and interest. This Mr Copleston is no relation but I'm not surprised to see the name in Devon as the village of Copplestone is located there from where the name derived around the twelfth century. Nice to know that the chess playing gene is widely spread though.
I've now come to the conclusion that the box pictured was not related to chess, but highly likely a 'valet box' given the circumstances of a 17 yr old leaving home. There are similar items shown online.