Hi Andy
I think you are very lucky man. If your glasses is for sale in my auction house l think it will not sell for more than £40. I have been collecting drinking glasses for sometimes now. These type of glasses is not old enough for collector like myself and the only buyers are buying for personal use. Personally, l have my doubt about the age l would put them in 1940/50/60.
Sorry for being too harsh. But that is the reality.
On the lighter note. Today l went to the Glass Museum at Stourbridge while my better half spend my hard earned cash in Merryhill. It was a very enjoyable two hours and it was free. There are books and quite a few types of studio glasses for sale. Highly recommended if you are over here in future.