This guitar came up for auction in December 2013 and sold for $1,599.
"Here is one of the original Ampeg Dan Armstrong guitars made in 1970. This one has the "CB" (country bass) pickup. The electronics work well but the switch has been disconnected from the circuit, so it has one volume and one tone and a diconnected switch that occupies its original space.. The neck has its original finish and frets and there is moderate fretwear but the guitar plays nicely as is. It has a good deal of fretlife left. It comes with this hardshell case which I do not believe is original. I have only seen the Dan Armstrong guitars with the formica pickguard but this black pickguard with the underneath white looks very old and I am tempted to wonder if Ampeg released any of these guitars with this pickguard."