Looks like it’s the downstream pipe from the exhaust manifold. I replaced the exhaust from that pipe all the way back. You will not need to do any welding, but you may need to use an angle grinder to cut it off.

Front pipe (where I suspect the leak is)

Catalytic Convertor

tail pipe

This should be all you need to replace everything from the exhaust manifold back. It should run you about $220 for the parts mentioned and exhaust clamps.

Don’t forget to replace the O2 sensors as well.