I tend to find its different what a supermarket stocks in different stores over the country. At one stage I could get the apple from my local morrisons, but I cant anymore. They do sell a strawberry & kiwi of their own brand but thats got citric acid in it! DURRRR!
Only place I have found the flavours is asda. They also stock the still strawberry & kiwi in BM's - better than the sparkling!