http://www.americansoda.co.uk/uk/American-Soda/Home/Drinks/Regular-Soda/Coca-Cola-Vanilla.aspx
Based in cheshire, used them before for mountain dew. Very good service. Out of stock at the minute, but the guy is constantly getting new stock and Im sure will give you an update if you send him an email.
Big Pint glass, A dollop or two of ice-cream, Pour coke over it.
All that? For vanilla flavoured acid???????
Looks like I was wrong.