Replacement hardware for steel closet doors

Thanks for reaching out to us. Looks like you have an old National closet door. The first photo shows the 21-041 pin assembly with a 5/16" 21-151 nylinder. The other pin in your first and second photos looks like the guide pin 21-072 with a 1/4" 21-150 nylinder. The third photo looks like the bottom threaded adjusting pin, the 21-046 and the last photo looks like the pivot bracket 21-204, which is now nylon. Look these parts over and see what you think.