3-1 oil in NZ cost me $11 at 'The Warehouse' and its only a tiny bottle.
There are a variety of oils that people use. Many here use ATF (Automatic Transmission Fluid). 3-in-1 makes an oil in a blue can for electric motors that is a 20w oil, and can be used in an S-A hub. Don't use stock 3-in-1, as it will gum up your hub. Or you can just use 10W30 motor oil. I bought a quart of synthetic 10W30 on sale, and poured some into an oil can for easy dispensing.