The numbers are pretty likely to be hard to swallow.
70 kilos of iron would come by seafreight.
It will probably be approx 0.1cubic meter.
Seafreight will probably be less than 50 dollars if your supplier sends it and You prepay the freight.
You will need a customs agent if the value of the shipment is over $1000 as customs get involved in shipments over that value.
This is where it becomes expensive as the agents fees may add another few hundred dollars on top.
Dont forget 10% GST is also due plus port handling and storage fees.
Best thing to do is to find a company in Your area that can do importation for You and inform Yourself of costs.
Alternatively You can do all this on Your own; it is an interesting excersise in bureaucracy but is worth doing it.