[Rick Parker]

New??? Used ones (1M) casting # should be readily available or through a volume engine rebuilder or many other sources, even ocassionally on EBAY. If you want NEW, you will most likely need to have it made by a crank shaft manufacturer, such as Crower, Cola, perhaps Scat or others......??
Have not seen any NOS 289 cranks.
A used crank will clean up at .010, .020, or as much as .030, undersize on the rods and still be larger than a small block Chevy so rod journal strength is ok at that size. Du to the small blocks inherantly good oiling system and the short stroke the cranks don't get beat up too bad, so finding a usable core should not be a problem.

Good luck

Rick