Welcome to the GMB.
If your celery vase is British, it is certainly not from any of the British registered designs that I am aware of.
There were also lots of British celery vases from unregistered designs but yours does not match any of the examples that I have come across either.
I do have reference photos for several examples of celery vases like yours (and always unmarked and in clear uncoloured glass) but so far I have been unable to provide an attribution for them.
Fred.