Thanks Pat,
I was hoping there would be someone on this site who would be able to point me in the right direction so I could get the new bearings and just put them it without having to take the old ones out and match them up. I thought they might be a standard-ish bearing that would fit a named flip flop hub. I always used to use Pearsons Cycles in Sutton but my work moved so I though I'd do it myself. I have stripped it down and greased the cartridge but there's still some movement so they'll have to come out.
It's probably safer to do it that way anyway or I'll end up with the wrong bearing.