Hi Hannah,
If you are able to, I recommend consulting with a professional conservator before you attempt any cleaning yourself. Without having seen the uniform (or photos) or evaluated its condition, it's difficult to say what cleaning can be done safely. After learning more about the uniform and the context, a conservator will be able to advise on the appropriate way to proceed.
You can use the AIC Find a Professional tool to see if there is a textile conservator near you. If not, you may be able to find someone who will travel, or as you said shipping can work too (they will be able to give guidance on the specifics of that). The AIC guide Hiring a Conservation Professional is a good resource, as is NEDCC's Choosing and Working with a Conservator.
If you opt not to work with a professional, this article on The Care and Preservation of Antique Textiles and Costumes has lots of good background information as well as a more detailed section about cleaning. I also recommend searching for "textiles" or "costumes" in the Connecting to Collections Care resources and exploring what's available there.
Please let me know if more questions come up, and thank you for your question.
Rebecca
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Rebecca Smyrl
Connecting to Collections Care Monitor
Assistant Conservator for Special Collections
UNC Chapel Hill Libraries
Chapel Hill NC
(919) 962-4250
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