I bought my Spectre II last week from Sooner State Pawn on NW 23rd. Todd at the store did the trust making it painless, fast, and free. He explained how the trust and the rest of the process works. I put my wife and son both on it with the wife as the successor. Now I'm just waiting.
This place has a nationwide business and if I remember right, they partner with Sooner state pawn for trusts. Visit their site that has a ton of video's, and make your decision.
I will throw a couple other names in the mix. Winton law did my trust and can't go wrong with Dustin gaunder of class 3 designs or steve at cold hand arms.