Anyone know where to get a 312 Crank for my wife?

[Ziffer]

My wife got her father's Thunderbird 2 years ago. She was very excited but as it goes with old cars it has been an uphill battle. Trans rebuilt, cracked flexplate, suspension/brakes........etc.

Had to pull the engine for a rebuild since the blow-by was so bad it was pushing the dipstick up out of the tube. Now with the crank out we have a 1 inch crack and since it is cast repair is not an option.

The 312 crank only fits a 312.

Any leads would be greatly appreciated.

Thanks
Z