What Mr. Bellamy needs is called "Polycord."  It is synthetic and is
cut to length and fused with a match or cigarette lighter.  It comes in
many sizes, but the ones Mr. Bellamy needs are offered by Small Parts
Incorporated, of Miami Lakes, FL.

Their website is http://www.smallparts.com/

I have used this material for many drive applications and have found
it entirely satisfactory.

Dave Vincent