JL audio components the new ones with built in crossover you get the tweeters 2 so you can change the tweeters in the dash and the speakers in the door are direct replacement its what im going to be getting soon well worth the money get them from sextons in swindon mate
I would get a new headunit as well, Sometimes have bigger amps inside so louder speakers.
Or you could go Alpine all the way be a good setup
Go into your local sextons and ask them bout the JLaudio components with built in crossovers there 13cm speakers come with the tweeters cant remember model but think there around the £100+ mark they should know which ones your on about they would sound mint mate then just get some JL audio 13cm rears and it sound nice. then get a decent Alpine headunit PUkka job