Sony Bluetooth Mobile Phone

I want to copy my phone book from Sony Ericsson T630 to Sony Ericsson K750i, but I can’t Bluetooth the whole phone book, because I have already done that and if I do it again, it would create duplicate entries for each contact in the K750’s phone book. I also can’t delete the whole phone book on the K750, as you need a pin, which I don’t know. Also it is tedious to manually delete every entry in the phone book on the K750. Is it possible to find out what the last 10 edited phone contacts where on the T630, so I can manually transfer them to the K750, updating the phone book?