Update: I ran across this product today:


<a target="_blank" href="http://www.bhphotovideo.com/c/product/532339-REG/Gitzo_GS5160CDT_GS5160CDT_Arca_Swiss_Type_Plate.ht ml/BI/3152/KBID/4157"]Gitzo GS5160CDT Arca Swiss-Type Plate to Gitzo Quick Release Adapter
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This might be what you are looking for.