Just thought I'd give you guys a heads up on this. I stumbled across this, and I hear they are quite rare. Butt ugly, imo, but quite a collectors item! I'm not affiliated with the seller, but I thought you guys might find this interesting.
[url="http://cgi.ebay.co.uk/Shergold-Marathon-Bass-Mk1-Handcrafted-in-London-1976_W0QQitemZ200138546421QQihZ010QQcategoryZ4713QQssPageNameZWDVWQQrdZ1QQcmdZViwItem"]http://cgi.ebay.co.uk/Shergold-Marathon-Ba...1QQcmdZViewItem[/url]
Enjoy!