You might ask Hammond - http://hammondorganco.com/
There's a dealer locator on their site.... might be one in your area - http://hammondorganco.com/dealers/
There is the possibility that Hammond doesn't make their own cabinets, but contracts some other company to build their cabinets. In that case, contacting the maker might help.
No matter what, more likely you will have to experiment with different shades of stain. As mentioned below (link), old stain recipes are hard to match.https://organforum.com/forums/forum/ele ... ond-stains
Google around, you might find something more specific to your needs.