Having just checked out the Hannants site squadron do a replacement part but for the Monogram kit. Now, if it was an internal part I might be tempted to try to make it fit, but as it is the windshield - the whole contour might be wrong. I've got nothing to loose in giving polishing a go - I've got cloths/papers from 600 to 12000 grade. But order a replacement just in case!
The fog seems to be on the smooth inside, so at least I won't have to worry about the frames.