Hi all,
If anyone is looking for thick-walled pipe for a pier then these guys in Toowoomba have a huge array of mining leftovers at different diameters and wall thicknesses:
http://www.nkf.net.au/steel_pipe.html
They will cut to any length and the price is simply the listed price of the full length divided by how much you want. The first two cuts are free (rough with oxy).
Of course you then have to pick up or arrange freight, but some good prices can be found through TruckIt.net and nkf will load on.