I think that the first few replies here were very disrespectful of what is a basic inquiry. There are many people who want to know which BK to get and without going through the players pages and reams of other questions, they can only ask in reference to sounds that they know. I see nothing wrong with the questions, and other than the fact that I have very little experience of DiMarzio pickups (and then only in the 70's), would be happy to answer.
There is no real BK version of a 'rails' pickup as Tim doesn't like the sound of single coil humbuckers (I am with him all the way on this too). I have put a JB jnr in a tele for someone, and so do know the sound of that, but the rails are a bit more driving I believe. A Piledriver is a great 'Broadcaster' sound, but is still a single coil pickup. If you could explain the sound you want (with some artists or tracks), then it will help to get closer.
For the Alnico II, you are spot on, a Stormy Monday with A2 magnets will get you there (and a lot further too).
Once again, if you can come up with some tracks, then we can give you more idea of what will work.