Here are two gimmicked-but-reelless versions of Ring Flight.
Closeup version: Sew a metal ring into an tiny pocket in a handkerchief. Open the keycase and hang a key on each keyclip except for one in the center. Open the center key clip, rotate it out, and close/latch the case with the clip hanging out, sealing the rest of the clips/keys into the closed case. Place in jacket right breast pocket with the open clip hanging out of the pocket.
Borrow ring from Spec 1 in right hand. Hold hank in left hand. Place the borrowed ring under the hank and into the left palm, simultaneously pushing the sewn ring to the center of the hank. Hold the substituted ring from the outside of the hank with the right hand, and give it to Spec 2 to hold. Reach into right breast pocket, threading ring onto single loose key clip. Remove the key case from right breast pocket with left hand covering the ring and clip, and hold the case in clear sight. As the hand exits the pocket, the keyclip end of the case is automatically turned to the bottom of the hand as the hand turns palm up. The magician reaches over and whips the hank from Spec 2, and Spec 2 verifies that the ring is gone. The hank is replaced in the magician's pocket.
Left hand holds up the keycase. Right hand opens the inverted keycase, and the keyclips clatter out in a row. There, in the middle of the keys is the ring on a key clip. After the spectator verifies that it is his/hers, the magician removes it from the clip to return it.
Stage version: Procure a small wineglass. Instead of sewing the ring into a cloth pocket, hang the metal ring from a short thread sewn to the middle of the handkerchief.
The magician might write a receipt for the borrowed ring to give to Spec 1. Substitute the threaded ring for the borrowed ring as before. Hand Spec 2 the wineglass, and guide Spec 2 to cover the whole bowl of the glass with the hank. As Spec 2 then drops the sub ring into the glass, the magician reaches into his pocket for the keycase. All eyes and ears are on the noisy clatter of Spec 2 at the moment of the drop, and the load of the ring should be well-covered. Spec 1 is then told, "If I lose your ring, I might need a quick getaway" as the keycase is removed from the pocket. Then the magician snatches the hank away, taking the sub ring with it, and places the hank into a pocket. The wine glass is empty, and Spec 2 verifies that the ring has vanished from the wineglass in his own hand. Spec 1 then sees the keycase opened, and verifies that his ring is hanging from the keycase.
I would think that this second version of Ring Flight would play better than Bill to Lemon on stage, as it is more magical for the distant audience due to the clatter noise of the dropped ring into the wineglass and the very visual/aural drop of the keys from the keycase.