This can has been kicked around recently.

 [ See the articles about CITES and ivory transport indexed at
 [ http://www.ptg.org/scripts/4disapi.dll/4DCGI/cms/review.html?Action=CMS_Document&DocID=608&MenuKey=Menu27 
 [ http://www.mmdigest.com/Archives/KWIC/I/ivory.html  -- Robbie

While there is always a chance that the Pierce Piano Atlas will be
sufficient documentation (depending on the agent who processes you),
there is a far greater chance that it will not be sufficient.  The CITES
treaty is in effect and imposes strict conditions for transporting and
selling artifacts (musical instruments) which contain ivory and exotic
woods.

I suggest contacting an experienced and knowledgeable person in these
matters, to see what you are truly up against.  I believe, for example,
that Rod Verhnjak in Surrey, B.C., does cross border moves on a regular
basis, particularly in CAN-US direction.  Visit http://www.pianoman.ca/ 

The best advice I can give is be aware of the regulations, and be
prepared.

And now, congratulations on your acquisition, once restored it should
serve you very well!  I am sure we would be interested to see before and
after photos.  Best of luck!

Ian Gillis