I want to send to a mate who has had to return to Australia and unlikely to return to Thailand some of his possession that he left behind in Hua hin.

He is not bothered about how long the parcel takes to get back to him and I suspect sea passage will be cheaper than by air.

The parcel weighs approx 12Kg and has the following dimensions: 50 x 50 x 20 cm.

Any thoughts on who to use for surface shipping? (BTW I have enquired at the Hua hin Post Office and they are only doing EMS and courier services by air at the moment).

Thanks in advance.

Let Mr. Google be your friend. "shipping Thailand to Australia" will give you many options in less than a second.