Azphelumbra.
If you bring Prototype War Supplies and War Points to [%dic:STR_DIC_N_IDEternity_War_D_WPSeller], then you can exchange them for Superior War Supplies.
Just know that you won't be able to use your exchanged supplies or War Points outside of Evergale Canyon.
Also, if you'd like even better War Supplies, you should talk to [%dic:STR_DIC_N_IDEternity_War_D_WPSeller_03].