I saw a nice one (68) on ebay a couple of weeks ago for sale. I don't think it sold.
It was in California too.
Search the ended auctions and you may find it. Email the guy and maybe he still has it.
Good luck. These panels and the sheet metal under them usually rots out, so finding one worth having in the bone yard is rare.
There are also a few El Camino's being parted out on the for sale pages of this site. Spend a few minutes shopping there and I bet you can come up with a decent one.