In reply to BlueTotem:
Considering what your doing with the wire, ie. building a slightly dubious snow anchor where the anchor will rip out or the shovel head will bend in two at relatively low loads, you don't really need crazy strong wire rope.
I'd get yourself to a ships chandlers, there's a powerboat shop on Gibraltar street IIRC, they may have something for you.
I'd consider using 5 or 6 mm accessory cord, maybe not as durable but plenty strong enough, much lighter, easy to get hold of and use and cheap as chips to replace if need be.