Any question answered...

There's a fecking great pro catering shop on Shaftsbury Ave. Not sure if it's open on sundays though.

http://www.allinlondon.co.uk/directory/1103/9627.php

I think I got one from the big Sainsburys in Dalston. Not sure of the specifics of the nozzles.

Cheers both, I slept in so didn't matter anyway. Heading central shortly so shall pick things up and perhaps post a photo of my efforts this evening.