Nikon MB-D17 battery grip for D500 now on sale at Amazon US - Nikon Rumors
Vivitar Battery Grip for use with Nikon D5300, 3300, 3200 and 3100 Cam – Camera Exchange
Neewer Professional Vertical Battery Grip Replacement for Nikon D3100/D3200/ D3300/D5300 SLR Digital Camera, Works with 1 or 2 Pieces EN-EL14 Batteries
NEEWER Vertical Battery Grip for NIKON Work with EN-EL14 - NEEWER