How has it failed,they are made of aluminium.Are you sure it isn't the gasket that has failed?
 
I agree with Andy, it's a lump of metal!

Depending on what has happened it might be worth getting it to an engineering shop and getting it repaired.
 
I have now been told it's not the manifold, rather the intake manifold flap?? Which is operated by a motor? Are these an expensive part or just a pain in the @ss to fit? :shrug: