World is your oyster mate. Emirates would snap you up for the 777, SQ would go for you for your 777 and 744, even better if you had PW4000 motors aswell.
But...depends what you want to do and why you want to leave Big Airways?
Financially if you have a family you might be better off in the UK.
As a single man or just you and the missus you'd have a ball in either Dubai or Singapore with the expat lifestyle.
You can also go out into the connie game as a hired gun and do 6 mths here, 3 mths there and probably make even more money...but working conditions will vary.
First thing is weigh up why you want to make the move and how do you feel about the cultural/work environment changes. I am sure you will be inundated with messages saying certain contracts are crap and some are good, but it boils down to what you want to do.
Drop me an email if you want more specific info.
Good luck