I'm not sure whether the one I use quite covers that area - definitely South Oxon anyway, and I would highly recommend her, she's called Nicola Desailly - google and you'll find further details/pm if you want more info.
Sadly my equine physio doesn't travel quite that far.
HOWEVER, please be careful. Talk to your vet. Look on ACPAT website. It is illegal for anyone to treat your horse without your vet's consent. MANY MANY 'back people' ignore this. The law is there for a good reason - your protection and your horse's protection. If you contact someone and they don't ask who your vet is, question whether you really want them to treat your horse.
Thanks for all advice, I wouldn't use anybody without them wanting to ask for vet consent first. I've used people in the past who have worked with vet consent and I would say that while anybody good won't work without vet consent the two aren't necessarily mutually exclusive i.e. anybody working with vet consent IS good! I'm asking here because I value personal recommendations highly there are vast amounts of bad 'back people' and very few good ones! Thank you peh1980 I'll have a look and see how far she'll travel.