Then you machine is not Korean is European, Ecotec 1.6L is ....
I can buy the pure hard thermostat without the lid, at least in Mexico is complicated to get the parts, because the engine only came here two years and only one model, the Pontiac G3, so all parts are expensive agency. ..
Changing the thermostat cover is cheaper than changing the entire housing of bakelite, that is part if the temperature gets too high, but still are not bad engines, there are machines that are broken with these heated ...