I am in SE London and use Oxted vets as they are good at coming out in an emergency - expensive call out but they are equine specialists. You can use Bell Equine, the hospital in Kent - they are great but I think prefer horses to be taken to them and I have heard that they aren't so good for a home emergency. That maybe hearsay though so why not give them a call. Farriers - I have used Eddie Dennis (used to come to me when I was in Chislehurst) and Mike Nuttall (Sevenaoks based not sure if will travel) tel 07802 2435760, both are great. Haven't got Eddie's number on my phone anymore, he's a really nice guy, was always on time and will try and come to you early so your horse doesn't have to wait in for too long.