Hello, and welcome to the HUBB. Attached to this bulletin board is a website with heaps of info. In particular, we have a page called Shipments which contains reports from travellers who have done a shipment and shared their experience. Singapore to Darwin by sea has been done, and contact details are at the following link:
Kuala Lumpur, Malaysia, is another good possibility, with reports from there into Darwin, Perth, Melbourne and Sydney. Follow this link for Darwin and scroll down for the others, including a good description of the procedures in Australia, which are stringent.
Shipping to Perth or Sydney will be cheaper than Darwin (which is a surprise!)
Lucas Yap of Freight Logistics in KL comes recommended by several travellers, and his contact details are noted in the KL to Melbourne post.
Good luck, and let us know how you go!
"It matters not what goal you seek
Its secret here reposes:
You've got to dig from week to week
To get Results or Roses."
'One world, two wheels'