Replace the manifold (quite expensive and I've heard due to the extreme heat the bolt may bust when you try to remove the manifold and then it turns into a huge job!)
I heard of a product that may be able to withstand the temp it's called Davcon Welders Plastic?
The car is an Acura 2.2CL 1997 if that helps.
A Reputable "Machine shop" will have the proper equipment and skills to weld the cast iron manifold..
Howevr, the costs may be higher than it would be to purchase another manifold new or from a salvage yard...
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