PotionMistress, ecl, Friendly flyer, and KevinBGoode thanks very much for the kind words :$
Just back from LeakyCon LA (Los Angeles), where I had the good fortune to meet and talk with Pierre Bohanna:
He told me that many of the actual suitcase props are cardboard, and the ones that are carried around a lot are carbon fiber to reduce weight. The "muggle worthy" mechanism movement is actually accomplished with a servo which resides inside a special case! I told him he cheated :rolleyes, and he thought that was funny. He did mention that, just eyeing it, my case needed to be about 20% taller - about an inch I guess. So if anyone else wants to replicate a suitcase, please keep that in mind. He did not bring any props to the convention.
Regarding the lining fabric, it took hours and hours of work to generate the PNG file, but I will share it with anyone who builds a suitcase from scratch (not an eBay find). Just post several detail shots of leather working to this thread (cutting, shaping, staining, stitching, riveting, and so forth), and I'll email it to you. It's 7 megs.
If there's general interest - I will show
how I generated the file for the fabric.
Also visited Universal Hollywood and met this young lady!
ATL