There are essentially two people who do the conversion right now, Ed at HDPS and Wade at Top-Notch Parts. Jeff at Tactical Excellence has done several members' conversions but he is not doing any more this year (and I don't think he's committed yet to doing any next year).
Wade at TN did mine, and while I am very happy with the work and the finished product, I had to wait over 3 months to get mine back from him (his advertised wait time is 10 weeks). Most people report Ed's turn-around time at 1-2 weeks.
Assuming that you're doing the non-SBR conversion (you're keeping the full-length USC barrel), you will need 3 "compliance parts" to make the rifle legal. Ed sells a compliance magazine baseplate and follower, however I'm not sure if his triggers are in yet. He may try to sell you a new barrel as the third part, if that's the case then ask for a trigger or call Top-Notch and get one of his and ship it with your USC to Ed.
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