I found a 32' Interfit cord on B&H for $49, but I remember seeing some cheaper so I will have to look around more. I am going to keep an eye out on Craigslist for a good used 580.
I bought the cheaper cord and was very disappointed in the build quality. I "bit the bullet" so to speak and bought the 33' cord from http://ocfgear.com/
and it is much, much better quality. I've broke too many plastic shoe mounts to use the cheaper model. Just my $0.02.

