To the best of my knowledge, no manufacturer is making a one piece oil pan gasket for a Big Block. Fel Pro has one for the Small Blocks, but no BB. The only exception to this is the 1991 and newer Mark 6 stly big blocks which come from the factary with a 1 pc rubber gasket. But this gasket is not usable on the older style motors, which I think is what you are looking for.
Advanced Automotive Machine
Bill Check out Detriot gaskets, I am almost positive they make one for use with two piece rear main small blocks. They told me at the AERA show in Vegas,they might do a big block seal. I don't know if it ever happened. The early small block seal should be available if they did not stop making it. The cost was about $18.00 and reusable like the new one piece seals are.
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