Hi - welcome to the GMB

I don't know that just the name is going to be sufficient for folk here to know exactly which design/pattern we're speaking of - if it's at all possible are you able to add a picture or two? - if nothing else it will be of interest to know if these are saucers/coupes or flutes. Many designs were produced for many years, and Stuart is a good example of that - some of the 1920s patterns - Woodchester and Stratford Rings for example, were produced for many decades. Assume your request is to know when St. George was first made.
Giving patterns a name - in addition to the factory pattern No. - is possible more a modern feature - maybe possibly a post '70s thing.
Personally, I've never heard of St. George (as in Stuart glass), and this may be a very difficult request to solve - and in this instance I doubt that the Replacements web sites are going to be of any help. Fingers crossed someone here may be able to help.
The Mods may wish to move this one to British and Irish glass.