Until I retired, I worked for P&O Nedlloyd for 22 years. We carried a few boats to and from Aussie on deck in open flatbed containers. If the boat was overwidth of 8ft, it took up three slots wide. Maximum length on a containership is 40ft, although they can accommodate longer. I believe P&O Nedlloyd ship from Tilbury on the Aussie trade.
If you contact the address and phone number below in the first instance, they will give you further contact numbers for the information you need.
P & O Nedlloyd Ltd (Container Shipping)
Beagle House, Braham St, E1 (020) 7441 1000
FAX (020) 7441 1500
Although this depends on where in OZ you are and what day. For a bit of amusement have a look at www.fuelwatch.com.au to see how much it varies! From Friday through till Monday it is more expensive than Tuesday till Thursday so the weekend beach goers get hit.
I would suggest you have a look at ... www.boatpoint.com.au to see how much stink boats are here. I bet you are better off selling over there and buying here in OZ.. ( remember there is import duty etc)'
Others have given you the petrol prices.