Thanks for the info. I looked up on ebay and at the moment, couldn't find any old or broken charmer. Will go and ask at T-mobile shop first, if they have it and if they charge something like 40 quid, won't get it.
Then will start going for other options like modifying the case to fit any other speaker.
Anyway, contract about to finish in 3 months or so, so maybe will just leave it like that and get a new phone when contract finishes.....