God, I hate this pile of shite

[mr self destruct]

Are you 100% sure it's the head gasket gone? The coolant system is under pressure anyway as it runs at over 100 degrees. It's sealed in order to raise the boiling point of the coolant, so it can do its job more efficiently (just like a pressure cooker). It could just be knackered pipes as they go brittle and split with age, so don't write the car off just yet.