I've always been told there was a shortage of experienced engineers in the UK helicopter industry and even our company has trainees on apprenticeships right now. I think you're best bet would be to get a copy of the BHAB handbook etc and just write to as many organisations as possible. The UK is in a bit of a downturn right now with helicopter use, so maybe not the right time to be seeking employment here, but if you don't ask, you won't get. Good luck.