This item is not included in any spawn asset, but it doesn't necessarily mean that it doesn't spawn naturally on any of the maps.
PS_Helicon_Rocket.dat
GUID 77eb2807208a4009b6186433b26de535
Type Magazine
Rarity Legendary
ID 10904
Size_X 4
Size_Y 1
Size_Z 0.25
Amount 1
Count_Min 1
Count_Max 1
Calibers 1
Caliber_0 10905
Delete_Empty
Blueprints 2
Blueprint_0_Type Ammo
Blueprint_0_Supplies 1
Blueprint_0_Supply_0_ID 10904
Blueprint_0_Build 30
Blueprint_1_Type Gear
Blueprint_1_Supplies 4
Blueprint_1_Supply_0_ID 19351
Blueprint_1_Supply_0_Amount 1
Blueprint_1_Supply_1_ID 19352
Blueprint_1_Supply_1_Amount 1
Blueprint_1_Supply_2_ID 19680
Blueprint_1_Supply_2_Amount 3
Blueprint_1_Supply_3_ID 19567
Blueprint_1_Supply_3_Amount 1
Blueprint_1_Outputs 1
Blueprint_1_Output_0_ID 10904
Blueprint_1_Output_0_Amount 1
Blueprint_1_Tool 19374
Blueprint_1_Tool_Critical
Blueprint_1_Build 27