Is the Food Co-Op at 58a Crampton Street still open? I used to use it when I lived in Julian Markham House (the building above Dragon Castle). I keep forgetting to check if its still there. It was a very old-school food co-op housed in a former corner shop, and seemed to be a bit of a counter-cultural centre. They had very eccentric opening hours, but worth a visit.
Shopping there could be frustrating, and the politics sometimes prevented actually buying anything. They don't provide bags of any kind, not even paper ones, and they got very snippy and self-righteous when I asked for some on my first visit. I had to go home and come back with Tupperware and little paper bags, which is good to encourage, but it's silly actually have NONE available to less organised shoppers.