I would get it rewound. It will sound better than any new pickup and it will be the original pickup. Keeping it in a box just seems sillyYeah the more I think about it, I'm leaning towards a replacement and putting the broken pickup away.
I was looking through my copy of "The Beauty of the 'Burst" and the author has some interesting theories in the back of the book on the unique tones of PAF humbuckers. One of the points that he discusses that I think also applies here to single coils as well is in a section called Bobbin shrinkage and distortion.The bent top is not an issue... I have seen many (still functional as well as rewoundl) 50's pickups with curved tops. It's also not likely to be the cause of the pickup breaking.
In my experience extensive rust on one the outer magnet poles indicates the coming end of the pickup unfortunately. The corroded pole piece destroys the coil wire from the inside eventually.
meanwhile, seymour duncan charges a premium for deliberately rusty polepieces on their antiquity pickups. Genius planned obsolescence strategy? Or not a big deal after all?Rust is NOT a problem. Note the extended middle poles.