Here is a list of Resources that are not available on planets in game but are listed on Galaxy Harvester.
Bristley Hide:
Dantooine, Mustafar
Leathery Hide:
Scaley Hide:
Lok
Wooly Hide:
Dathomir, Mustafar
Meat:
Avian Meat:
Dantooine, Endor, Mustafar
Carnivore Meat:
Mustafar
Domesticated Meat:
Dantooine, Dathomir, Endor, Kashyyyk, Lok
Herbivore Meat:
Mustafar
Insect Meat:
Dantooine, Lok
Reptile Meat:
Corellia, Dantooine, Dathomir, Endor, Rori, Yavin 4
Wild Meat:
Lok, Talus
Milk:
Domesticated Milk:
Corellia, Dathomir, Kashyyyk, Lok, Mustafar, Yavin 4
Wild Milk:
Mustafar
Bone:
Animal bone:
Mustafar. (this one I am not sure of)
Avian bones:
Mustafar