I haven't had the need to use one, so I don't know of any personally.
I checked the Yellow Pages on the off chance though, and sure enough there were forty results for "Dyers" (including one in the street I live in ). Some of those are not likely to be useful ([name] Carpet Dyeing Services for example), but if you haven't tried ringing around to those places yet, it would probably be the best place to start. There's also a lot of Textile Mills listed, and it seems possible some of them might be able to help you.
google search for companies in the US. Youll find some but the cost will be a lot more than from overseas.
Also look in the back of trade magazines like Impressions, Printwear, screen printing mag. You might find some, maybe just tye dye but they might be able to help as well in directing you to someone locally or at least in the country.
I just joined the forum today, but if you are still looking for a dyer, here is some helpful information. I once used a company down in Gaffney SC by the name of Garment Technology. They have a very knowledgeable staff, I spoke to Joe Gaino, his phone number is 864-487-5760. THey did a very decent job for us and their price was very fair.
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