Gill,
If you are looking to get some that would be appropriate for 6 volt, and copper clamps, they are available if you look online. Below is a link I found for some, and the clamps look a lot like the ones in squeeze's picture. They're 4 gauge - the ones for $86.00.
Samantha
Battery cables with copper clamps


1954 Chevy 3100
Picked from the Field
Follow in the DITY