How did the shop test for blown headgasket? Is it a shop you trust? If you aren't using coolant, overheating and the oil looks good it might not be a headgasket. If its leaking coolant to the outside of the engine and making puddles on the ground make sure all your hoses are good, Landcruisers have a PHH(pesky heater hose) that likes to leak and its hard to see where its coming from, yours is due on mileage and age if it hasn't been done yet. You might want to get a second opinion on the headgasket. Ask around on here or a local forum and see where the Landcruiser guys are taking their stuff and then go there yourself. I am a mechanic and have done lots of headgaskets and they usually have some driveability concerns to go with them eg: milky oil, overheats easily, blows radiator caps off, bursts radiator hoses, splits radiator end tanks, runs rough, has no power and misses under load, uses coolant, white smoke out my exhaust even when after driving a few miles, etc, etc.