with cut glass, the available patterns run into zillions, and in the absence of a backstamp, label or easily recognizable pattern, you're onto a loser really - which is possibly why a lot of people avoid the stuff.
British cutting patterns tend possibly to be bold and more simple in their geometric appearance, whereas Continental pieces carry more of this close patterned almost floral looking work - and this is taken to extremes when you look at ABP cutting with all those buzzstars, pinwheels and hobstars.
If you have a couple of weeks to spare, you might try Replacements.com - probably give you a headache though;)