I just found this -- http://www.ebay.com/itm/200858649301
Original Apple OEM Flash Storage Drive for later upgrades to all 2012 Retina Display MacBook Pros including the:
Late 2012 13-inch Retinal models
MD212LL/A (2.5 GHz with 128 GB), MD213LL/A (2.5 GHz with 256 GB
. . . and the
Mid 2012 15-inch Retina models
MC975LL/A (2.3 GHz) MC976LL/A (2.6 GHz).
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