You know what?...this is about every single System 9 pinball supply!

Any way you slice it, you're going to need to learn some repinning for the harness connectors.
If it were me, I would probably just repair the original, but my advice to you is to just go ahead with buying the new supply and fix the old one for a spare. A new supply will give you long term reliability and get you up and playing quickly. Then in your free time go back and fix the old one, which at least needs headers, 5V filter cap and fuse clips replaced. See the section on GI repair and connectors at this link:
http://techniek.flipperwinkel.nl/wms11/index1.html

My friends Comet. He called me over to fix it when he bought it years ago. It had around 12 feet of brown lamp cord and wire nuts in the backbox. It took quite a while to unravel, one of the wires came back to where I started, totally bypassing the fuses.

Yeah, there's a whole thread of crazy hacks below. I mentioned the lamp wire one because it was just a spaghetti mess all around the power supply.

https://pinside.com/pinball/forum/topic/worst-hackrepair-you-ever-saw