If only the item could talk, now that's a statement I've heard a lot! It's a shame it can't, if it could then it would be the most interesting 'thing' in the world.
Yes, I had though about the fact that the item could have been handled by many different people, not to mention if it was washed then all the fingerprints could be wiped away so you wouldn't be able to see any earlier than that point on. The only other option would be scanning the inside of the suit, but then many people might have worn it so even that way you couldn't tell. Although, if you could work out who owned it, then that could be a start...
You seem to have quite a collection Neil! If I could have half the stuff you have by the time I'm a father I would feel that I had acheived something. Oh BTW just so I don't clutter your inbox feel free to e-mail me anytime between now and february about the suit(1930 pattern) as I know you didn't want to send the label in the Christmas rush