Noel, if you have no luck with finding the hinges and hooks and eyes
for the music box cases, you might have luck in Brighton.  I cannot
remember the name of this "antique clock restorer" but I found him
at yell.co.uk.  (Sorry, I am abroad at the moment and don't have my
address book with me.)  He seems to have (or had) some stock of antique
hinges and other metal ware.

There is another place you can try but again a blackout on name.  If
the chap in Brighton can't help, email me and I will see if I can find
the second person who could have something

Ren
Renaissance Le Corbeau