I am selling an old keyboard on eBay at the moment. I don't know much about its history, other than that it has come from a house clearance and was amongst a number of items donated to Oxfam. It seems to be unused, the keys are clean and there are no signs around the holes in the steel plate that would indicate it has ever been screwed down.
Hopefully it might be of use to someone here!
Marc de Salis