What a fascinating thread!
I don't have any original comic artwork (although I do have the original artwork to an LP called 'Grotesque' by The Fall) but I do recall seeing some for sale in a poster shop near Piccadilly Circus in London about 10 years ago. All too expensive for me at the time but I remember there being a Carlos Ezquerra 2000AD cover for sale with the old curved 'Featuring Judge Dredd' logo. It seemed odd at the time that the text (logo, price, blurb, etc) had all been glued on by hand rather than being done on a computer.
Does anyone know what ever happened to the Judge Death Lives artwork? Has any of it ever turned up for sale?