My vote.

Go carbon and go threadless.

Find out what rake / axel to crown you need and then go shopping...

This is a solid, sub $200 fork. http://www.ebay.com/itm/220839402009...84.m1423.l2649

I would also suggest a Wound Up (if you can stomach the looks) or a Reynolds Ouzo Pro if you can find one new or low miles. You need to be careful buying a used carbon fork... I've done it twice now so I'm not saying you shouldn't do it, just make sure you're comfortable with its history.

EDIT. I agree with others above, I would probably go up to 43 but not any further. I've gone back and forth between 43 and 45 and never noticed a difference...