There is Baghdad Cafe and Whisky Bar in long street.
It's a very nice somewhat upmarket place and they do serve hookah so I do not think they would have a problem with vaping.
I know the owner and will chat to him tomorrow over a single malt or two.
Find out if vendors can set up etc etc. I will also post pics of the venue for your consideration.
It is not the place you see if you google it!!!
They do have a kitchen for light meals tapas etc...
I appreciate that Long Street area might not be everyone's liking, but it is a very nice place.
yeah i think 80 people and parking may become an issue. but investigate and we take it from there,