Brengun has released some upgrade sets in both 1/72 and 1/48 scales for the Lockheed C-130 and KC-130J Harvest Hawk

The detail set [BRL72172] for the KC-130J Harvest Hawk [Hercules Airborne Weapons Kit] includes AGM-114 Hellfire Missiles and a AN/AAQ-30 turret and the under wing fuel tank the turret is attached to as well as the fuel tank pylon. Not sure what the other parts are for.
The landing flaps are designed for the quarter scale Italeri C-130

BRL72170 - C-130J Engine set – 1/72
BRL72172 - KC-130J Harvest Hawk – 1/72

BRL48112 - C-130 flaps (Italeri) – 1/48

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