I found the perfect fabric for the back:
Designer: Lizzie Kate
Fabric: 28ct Hand-dyed Evenweave
(color and brand unknown)
Fibers: DMC
Size: 5x6.25"
Embellishments: Mill Hill Seed Beads,
Miniature Snowflakes
& Runched Ribbon
Stitched By: Meari
Here are close-ups of the details: