Amazon.com : PENTAX Battery Grip D-BG8 Black for Pentax K-3 III Flagship DSLR Dust-Proof and Weather Resistant Construction with Capacity to Hold Additional D-LI90 Battery (37048) : Electronics
PENTAX D-BG4 Battery Grip for K-7 K-5 K-5II K-5IIs From Japan [Exc+] #1102952A | eBay
Pentax D-BG2 Battery Grip 39557 B&H Photo Video
Pentax D-BG4 Battery Grip for select Pentax digital SLRs at Crutchfield