They do have Irish moss listed on there website
You may also see everything they carry on their website.
Best answer would be too give them a call. I'm sure they can get it if they don't have it, they have tons of things that I've found are hard to find. Good luck!
To be honest I am a customer that went there for teas. It would be best to call them and get the info that you need. I'm sorry that I don't have that info for you.
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