Bangkok Bank is usually the easiest but you will be asked to take their accident cover too, around 5000 baht but a small price to pay considering it's getting increasingly difficult to open Bank accounts now.
From the UK why not use a money transfer company such as Key Currency, very safe and they ask you if you agree with the exchange rate before they send it or you can wait until it's more favourable.
If I was you I would get myself home as soon as possible and resign myself to never traveling anywhere again unless it's in walking distance and the vibrations of your foot steps don't harm you.