I am quite interested in this too.. I'm not pregnant yet but I'm really desperate for another child at some point but put off by my first birth (scary emergency forceps in theatre with a huge episiotomy) and, although I'm not 100% whether I'd like an ELCS, I want to know what options I have iykwim?
Here in the UK, the NICE guidelines state that you can request a C-section for non-medical reasons (although, imo, previous birth trauma IS a medical reason) and if, after counselling persuading you not to plus other options offered to you, you still want it then you have the right to be given one. However, I have heard about some ladies being refused one when trying to get one on the grounds of a traumatic birth, but then some ladies get granted them quite easily.. so I'm guessing it depends who you speak to, the hospital etc.. just luck really.
Hopefully it won't be a problem for you and they will be fine with it.. if not, then it might be a case of really putting your point across, and fighting to get your elcs, I think if I was trying to win a case for an elcs next time then I'd really emphasise how the experience ruined my first experience of having a child and parenting, caused awful PND, made me stop breastfeeding etc. I hope you get your elcs. xx