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The palm-to-palm exchange with coins is Earl “Presto” Johnson's. See Genii, Vol. 73 No. 12, Dec. 2010, p. 73.
The single-handed switching of objects for one another dates back much farther with dice. In a book warning readers about the dice cheat, Gilbert Walker mentions the one-handed palm change being in use at the time. See Walker's A Manifest Detection of the Most Vyle and Detestable Use of Dice Play, 1552, p. 24 of the 1850 edition.