If it's truly KSC it should have "MANUFACTURED IN TAIWAN" or something to that effect somewhere on the pistol likely in some random hard to see place. Both "Taiwan" and "Japan" versions will say this, just the Japan version is for the Japanese market due to their energy limits (1Joule).
Looking at the reference pic however (if it truly is "KSC") it seems to imply that it's KWA as KWA is made for the US/UK markets and due to US regulations orange tips are required as you can plainly see on the box the gun has an orange tip. However to the best of my knowledge KWA has never made a Desert Eagle.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE