How about a 3-ring gag bit? It has the same action as a wonder bit.
Happy Mouth Double Jointed 3-Ring Elevator Bit - Dover Saddlery
Rotary Double Jointed Two-Ring Elevator Bit - Dover Saddlery
French Link Loose Ring Elevator Horse Bit, English Horse Tack
Korsteel 3-Ring French Elevator Horse Bit, English Horse Tack
I found one with a "moon" link in the middle.
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