I have a 59 Ford Galaxie 500 with a 352/390 engine. I have a busted driver side manifold. Can another year manifold
replace the one on my 59. Not having any luck finding one for a 59.
See attached pic.

 

We used to call them junk yards, today they are called salvage yards.
They usually can tell you if they have what you need and many times also tell what years will fit.

There are many vehicles in a salvage yard that are in better condition than some on the road. lol
Worth a try..

 

I can weld another ear on, and surface cut the face/flange. that way you retain the casting data...

 

See attached picture. Can you repair this?

 

A good machine shop can weld it and finish it

It would be a good idea to check a few first.

Cast iron requires a special preheating before attempting to do any welding and they are usually prepared to handle this.

 

Cast is welded with Nickel rod.
Preheated and peened during the process to control cooling/cracking. Welded many manifolds.
Sometimes they would crack on the thinner outer/inner faces between the ports, or vertical cracks on the outer surfaces because the cast has crystalized from heat over time. In those cases generally it's not repairable. But a broken ear, can be repaired fairly easy. Once repaired, the manifold 'must' be fly cut/surface machined so that it's perfectly flat.