My '85 has had shock cord from a backpacking store (REI?) since around 1987. Select length and tie a double knot at each end of each cord.  

Added bonus: I set one length at the factory setting, and the other at "just shy of tipping out all the contents". I can easily disconnect the short cord if I need greater access to the box contents. 

Karl Wolz
Sent from my electronic umbilicus

On Jul 6, 2013, at 2:17 PM, Stuart MacMillan <stuartmacm@GMAIL.COM> wrote:

> Anyone either find a source for these or fabricate a good replacement?  They
> often broke on my '84 and the same thing is true on my '85. I'm thinking of
> using cable with swaged ends or even knotted cord if these are NLA.
> 
> 
> 
> Stuart
> 
> '85 Westy