My Car Exploded! - I Need Help Please!

Hello to all who read this. I had a very bad day today. My 1967 Nissan Patrol's water/coolant pump decided to explode on me today. There are around 500 of these rare cars left in the USA, and i can't find parts ANYWHERE! It literally went down like this: I go in after fixing an oil seal (i had to HAND CRAFT the oil seal) I start the car, seems fine, no leaks, so i turn it off. I change the oil, clean the carburetor and add a few lights. Everything went fine. So i decided to drive it around the building a few times. The second i start the car, it starts leaking, and i didn't know, halfway around the buiding (20 feet) half a gallon of coolant comes out, and i am oblivious. I come back around, and i park it, it's smoking like crazy and i'm freaking out. I open the hood and water is coming out of the pump like a fucking fountain. I had the pump rebuilt a year before, this was EXPENSIVE! 300$ for it to be rebuilt, the bearings were 80$ EACH!! Then seals, labor, and lots of bullshit. It didn't leak one bit, and now it's fucked, due to it's old age. I cannot find one pump for this goddamn car, and i need this car, it's my bae. Please, i'm begging anyone to help me, i really need this, ANY info is helpful. Thanks!