454 Exhaust Advice / Help

[Mapearso]

So the headers on my truck just won't seal right. I've tried new / better /double gaskets, etc, but it looks like the headers are just warped

Instead of buying another set of headers I am thinking of going back to factory manifolds. The truck is just a cruiser and I don't need the noise and I am hoping factory manifolds will fit better

My engine is a mostly stock, mid-70s 454. What is the part number for the factory manifolds? Anything I need to be aware of? I assume the later ones from the early/mid 90s will NOT fit? (I know I can find these at a junkyard)

Thanks for the advice