You might want to consider a material made from carbon nano-tubes which have the property of shielding those frequencies as they are fairly conductive. This has the added benefit of NOT being an obvious shielding material which would be completely incongruous with a 'luggage' application. These materials containing vacuum deposited metals particles might be more appropriate.
http://www.metalcoat...CFDatasheet.pdf
Metal Plated Conductive Carbon fibers (MPCC)
http://en.wikipedia....atrix_composite
Might even consider using the relatively cheap reflective products here: http://compositeenvisions.com/