I have a similar issue. The fork on my Raleigh marathon was bent, and through progressive attempts at realigning it and getting it to be straight, it has actually formed a very subtle S shape. It looks good enough to ride on, but feels like crap.
So, with a 27" frame, my fork has an 11.5" steering tube. None of the forks on the two links above come with lengths like that. I'm actually not inclined to spend big bucks to replace the fork, since the whole frame (while perfectly decent for a single speed commuter) is not all that amazing.
Thoughts or suggestions (or extra forks)?