SepUtil is a Win32 utility for modifying SE Linux sepolicy files.
This is very much a beta currently and will be expanding rapidly. Right now, it can dump your sepolicy file into thousands of lines of printout. With that guidance you can do small modifications to sepolicy manually using a hex editor. In the future, you will be able to add types and modify rules more conveniently. In any case, it provides an educational insight into the sepolicy file.
You can use imgutil to extract or replace sepolicy from a bootimage.
Download the executable.