Easy way to make a dead Amanda is to cover her face with a veil. As for the sword, extra shiny duct tape and cardboard can work wonders.
though you don't have to go that far really. With are "I killed Amanda Palmer" ring there were four of us, each with different, simple weapons. Mine was a pair of scissors, Jordana's was a rubber ducky (shoved it down amanda's throat), Nicola's was a noose, and (rob?)'s was a pair of striped stockings.
Remember, she's weird! it's her trademark (seriously, have you seen photos of her house? She's amazing at the creative clusterfuck that goes along with keeping EVERYTHING that inspires you), so you can be weird with the concepts of her death.