hello and welcome from me also........ Am I seeing things, or is that the remnants of a label on the glass?? can't quite make it out, could be wrong.

I'd agree with Lustrousstone - it does look very typical of pieces from that factory - the shape of the stopper and the masses of gold banding etc. This style of decanter sets seem to have been made mostly after 1950 - and were excessively common and successful for a decade or two - they now appear to have become popular again as a retro fashion.
Assuming made over half a century ago, the chances of finding a replacement glass are almost zero I'd have thought - the glass replacements companies that offer on the internet don't, to the best of my knowedge, offer this type of material - the reason being that there is little commercial value in them, usually.