I’d talk to your harp manufacturer about shipping. They most likely have more knowledge and connections anyways. Either company in Chicago has likely dealt with similar shipping before.
The problem your most likely to run into is if the Harp will be delivered to Panama by boat or plane. I’m thinking plane might be the better option. I just don’t recall many ships doing any unloading before/after traversing the canal.
Another option is to contact the American embassy in Panama. They might be delighted to help you find a way to bring an American made harp into the country.