I need a new positive battery cable. Can you get them from Checker, etc, or is that a ford only super expensive item? Any idea on costs?

 

Why not build your own?
You can get the supplies at Interstate battery and cable all the way up to 4/0, bigger than your thumb.

This is thier website. http://www.allbatterysales.com/
But it's kind of not-so-good.
No pictures. I always talk to the local rep and tell him what I want and he sends it to me. They have top quality tinned brass connectors in any size and shape imaginable.
I use welding cable, it's nice and flexible, easy to route where ever it needs to go.