Have you checked out the soundboards on starwars.com? It might be easier to use those since there is no background noise or music. But then again, it might be harder to actually use them since you can't download them or anything (as far as I am aware). But it might be worth a try, especially since you can mix different lines together on the site.
I don't know much about this kind of stuff though, so I'm not sure if it would work or if it's been mentioned already.