Hehheh, unfortunately, I had to fill out papers and whatnot.. But the funny thing is that on the paper it says it's only worth $3,000. (I don't know how much that is in pounds, sorry) But that's cheap!
The King Super 20 Baritone are fine saxes. Doug James (former Roomful Of Blues member, Sax Gordons bari partner, Duke Robbilard Band ...) played a Super 20 bari for a long time. He is nowadays on a Keilwerth.
The funny thing is: Why didn't King offer the Super 20 bari as a less advandced bari version after they drop it as a prohorn? They had the tools and the knowledge. In the 80's King offered the market a bari with split bell construction! I think that's a construction from the 20's.
If you can buy a good King Super 20 bari for 3000.00 $, I think you should buy it. Or keep it and play it, meanwhile start saving up.