The first tanker was...

The first tanker was

http://www.lngworldnews.com/picture-of-the-day-seri-bakti-at-glng-terminal/

being optimistic she's around 75,000 tonnes. (152,000 cubic meters)

Back of the postage stamp calculation follows

@~$665/t => $50,000,000/tanker, Santos has 30% of that Gross Value

so 110 odd tankers per year are need to match T1 production of 7.8Mt.



Notes:

LNG is Natural Gas cooled down to condensate at -161^oC (-258^oF).
Natural gas consists primarily of methane. Impurities and heavy hydrocarbons from the gaseous fossil fuel are removed before the cooling process.
The density of LNG is roughly in the range 410 to 500 kg/m³. The volume of the liquid is approximately 1/600 of the gaseous volume at atmospheric conditions.