CCM no longer makes carbon fiber barrel kits for the Phantom. Your only hope is to find a used CCM kit, or one of the other, rarer barrels (made by CCI, Punisher, and Deadly Wind). Another option is to buy the Phantom threaded Freak back, and put a Stiffi tip on it.
As for other barrel kits, J&J makes a good quality one, and Lapco makes good barrels as well. You could also get your stock barrel bored to accept Freak inserts. This can be done by White Wolf Airsmithing, O'Dell's, VKC, and others. Alternatively, I know that White Wolf keeps bored out barrels in stock, so you could just order one.
If all else fails, your stock barrel with a set of detent rings will work just fine. That's a much more cost effective option, and you don't sacrifice much (if any) performance. Best of luck to you.
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