You've got time. Can't you make them?
For the wings, Coat hanger wire, netting/ white or other coloured lining material with a bit of satin and some silver or gold sprinkled on.. would save a lot. Not worth sewing, use a glue gun or glue.
And another bit of coat hanger wire for a chaplet, or Claire's accessories for a tiara..
And for the skirt, either more lining material with elastic waist, 20 mins work, or stiff netting, cheap shimmery top, more lining material or netting for a cloak.
If you want the Fairy Godmother look, you need darker material for the skirt and bodice, a red cloak, a tall hat (black card ideal) and a long stick.
(Gets all enthusiastic, the craft crew would advise...am sure Dd would love to "help". Guess who made the knight's and Robin Hood costume, the ninja turtle etc, not well but well enough. )