New Meyle air cleaner bracket is designed better than original-help me with oil leak

[willrev]

Was replacing my air cleaner bracket this morning. The new Meyle brand replacement seems heavier duty steel than old one. Original one broke on the rear top bolt. I put on a salvage one from parts yard car and two years later it broke in exact same spot. New Meyle seems ;ike stronger steel.

Noticed when I removed old air cleaner bracket that when I looked under the metal intake manifold that I could see where the top half of the engine connects to the bottom half - there is a seal there. This is where most of the oil is leaking on my engine. It is not coming from the valve cover gasket, but whatever seal that is between the upper valve train and the lower engine.

Can anyone tell me what seal that is and approx $$ and trouble to replace it?

Thanks.