283 Harmonic ballancer

Hello, I have a Chevy 283 in a 1963 Chevy truck with a harmonic ballancer problem. When I got it, it had the hub and pullies, but no ballancer. It ran just fine w/o it exept the bolt that held it on broke off and repeatedly kicked off the belts. Me and my dad drilled it out and tapped it for a new one. He found a h/ballancer off another 283 and we tried to put it on. Now the belts won't line up. I read somewhere that certain cranks were given only the hubs off the harmonic ballancer.
Also I need to know what kind of key went into the key way because with the bolt broke, the hub moved back and forth wearing out a large section of the keyway on it and it really battered the key on the crank. We got it out but we went to both Auto Zone and Oreilly's and they could not find the right one. Our key is about 1/4" tall and about 1 1/4" long. It is flat on the bottom and the top of one end curves up. The others that we where shown were about 1/2" tall and flat on top. :confused:
I don't know what year engine this is but it does have the block-to-frame clutch linkage so I'm guessing early to mid 70's.
So with this small problem, I AM VERY CONFUSED!!!!!!!!
Any help would greatly be appriciated. :3dSMILE: