I know that for the ones at Art of Animation (which were sold in their gift shop for awhile, about $125 a piece), the CM told me that they were custom made for AoA, in the USA (!) and that is why they were so expensive. Not a mass produced item, that would keep costs down.
It is possible this is the same for the GC, that it is custom fabric. (I did not buy the AoA one, I just asked about it when I saw it behind the register there).
They may sell them eventually (used, or even new unused spares) to the cast in DL, when they do a soft goods refurbishment.