Anybody know where I can find a 5-pin cable for less than $150?  I don't mind building one, but I don't know where to buy the parts.

Any decent electronics store (i.e. not Radio Shack) should be able to get Switchcraft A5F and A5M connectors or their Neutrik equivalent.  They should also be able to get the Belden 8424 cable you'll need (I believe that's the correct number, but you should look at yours to verify).  In a pinch, the Switchcraft A6F will work in place of the A5F, and seem to be more available in amature radio circles (I picked up a dozen new Switchcraft A6F 90-degree angle connectors for something like $5 not too many years ago at the Dayton Hamvention - wish I could find them so I could send you one).
John

Try Markertek.com for the XLR male and female connectors. Item no. NC5MX & NC5FX. They may have the Belden cable 8424. I have a 10 foot piece of 8424 cable if you want it. It would be a short cable.
Howard

Thank you for the offer, but I think I need a 20' cable.  My electronics guy is confident he can find it.

Andy - Check your email.
 
Michael