NEED HELP! '03 ALTIMA EXHAUST MANIFOLD CRACK

Hey guys,

My 03 Altima 3.5 has an exhause manifold crack. It makes a hollow rattling noise around 1500-2000rpms. My mechanic said I gotta replace the exhaust coz the manifold is connected to the cat converter and it’s only a nissan part and would cost around 900. Does anyone know of a simpler fix or where I can get the part cheap or get it fixed for cheap? I live in Hamilton.
Thanks

I have a question for you, is the crack on the manifold or the pipe to the cat?

problem already fixed. thanks