If any manufacture was to make that from a casting they should be immediately shut down.That piece is cast. If you were able to reshape it, I wouldn't trust it's integrity afterwards.
Replace it
That most definitely is a steel alloy forging, cast iron would not come close to holding up to the abuse that spindle takes.
Nor would it bend like that, it would shatter. Oh and even cast steel would not be used, it just wouldn't have the strength.