TaoTao 150 exhaust header/port mismatch

I lost the nuts off my header which I have replaced but obviously there was something else in there to seal the port. Some sort of gasket or WTF? I don't get it. The header does not match the exhaust port at all. It's like it's twisted. Some melted plastic there where the port is leaking.

http://i.imgur.com/YyAKJAk.jpg

Anyone know what goes in there to make the port not leak?

Looking at replacement gaskets I wonder if TaoTao actually mounted the gasket sideways. Then it fell out when the nuts came loose. That's the only explanation I have. I might just order a normal gasket and try putting it in sideways.