Varies a lot.  I've dealt with two restorers: The Musical Wonder House
in Wiscasset, Maine, and Nancy Fratti, in White Hall, NY.  The Musical
Wonder House is relatively fast: about nine months for restoring a
drum-and-bell cylinder box.  The problem was, they didn't do a very
good job of it, and I wound up taking the box to Nancy to make it
right.

I gave Nancy another box a year ago last summer, and I expect to see it
sometime this coming year -- but, I expect it will be right when I get
it back.  My experiences along these lines were written up for this
list and are available in the archives at  www.foxtail.com .

Regards,
Larry Smith