congratulations on your pregnancy and I hope I can help a little with understanding the system here
NHS care is the same for your pregnancy regardless of how the birth is going to be - ie most of your care will be done by midwives in the community, rather than in hospital. Many NHS Trusts would recommend you have another C/S this time round, and you would probably see a consultant once or, sometimes, twice during your pregnancy to discuss this, as well as your normal midwife appointments. Of course, if you actually decided you wanted a vaginal birth, you may also be supported in this (depending on your circumstances).
On the NHS you don't choose a consultant, you are assigned one, and the one you see antenatally won't necessarily be at your c/s. Uncomplicated caseareasns are often carried out without a consultant present.
Sorry I can't recommend a consultant at Chelsea & Westminster as I don't know any of them
Another option to consider is having private midwifery care, where you see private midwives for all your pregnancy and postnatal care (which is much more nurturing and time-intensive than most NHS care), and they come with you to the C/Section too, so you've always got someone you know and trust with you. you also get very intensive postnatal care to help with feeding and recovery. Most women in the UK have no idea they can choose their own midwife, but nearly all that do look back at it as incredibly helpful and worthwhile
all the best with everything, and feel free to PM me with any questions
Julie (private midwife), http://www.neighbourhoodmidwives.org.uk/