Hello Rowena
U.S. Art, Artex, Atelier 4, Artemis Fine Art Services and others provide fine art shuttle service throughout much of the contiguous United States, as well as provide packing services (for example, U.S. Art has a crate shop in Randolph, MA). All or most of these companies have a form on their websites to request a transport & packing estimate. Be prepared to provide dimensions for the artwork to be transported and packed.
Regarding packing, depending on age and condition of painting, you may be able to simply have it "soft-wrapped" in a corrugated board shadow box, which is less expensive than getting a wood crate fabricated.
I hope this is helpful.
Best regards.
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Noel Valentin
Permanent Collections Manager
El Museo del Barrio
New York NY
nvalentin@elmuseo.org212 660 7120
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