Possible Clues:

• Donkey confined by restraint in a Scotch container?
• O'Casey's cup, from which one sates drunkenly?
• Sean O'Casey wrote ''The Silver ......''
• Sean O'Casey play: ` `The Silver ......' '
• The silver for O'Casey to get the silly one in a knot
• 'The Silver ...' (Sean O'Casey)