retipping for Grado The Reference high output cartridge

Thinking about getting a retip done on my cartridge.  I know of someone in Brooklyn, NY and someone in West Hartford, CT and I believe Peter at SoundSmith might do this kind of work.  Any recommendations?
I didn't think Grado provided this type of service.  I'll check with them.  Thanks.
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FYI, Grado does not provide retip service, but rather a trade in offer.  That would cost me $1,000, so not what I'm looking to do.   Thanks anyway.
Steve at VAS is highly respected, shows lots of experience on his web site, and was very friendly when I have written and talked to him, and sensible advice when I was considering buying a MC that would need retip.
Andy at The Needle Clinic can do that for you much more quickly than Sound Smith.  I got my cartridge retipped from him and it took exactly a week from sending it to receiving it back.  I paid $200.00. 
What's the point to buy Grado cartridge if you can't service / upgrade with the manufacturer and can accept third party vendors as an alternative ? 

Then Grado with user replaceable stylus could be better for you, something like MCZ or XLZ (they are great). 
Dear @bdunne  : Very good cartridge you own, stay with and send to any of those posted re-tippers.

Regards and enjoy the MUSIC NOT DISTORTIONS,
I don't know why Grado only offers new purchase as an option on their most expensive cartridges.
I don't think the lesser versions that you mentioned would be in the same class as The Reference.  I've owned so many of them; the real basic ones, the gold, even the Sonata is not as good.
Grado just like any good manufacturer do not retip, they get your old and give you new cartridge with special discount (only if you send your old cart to them). 

Grado XTZ is Signature Model, top of the line cartridge from Joseph Grado himself, it's his best, but discontinued model (styli still available). Can be different from you model, but it's a killer cartridge (I've mentioned that only because it's the best Grado with replaceable stylus that I know and own, the stylus alone is about $500).