June release, 2,310 Yen (inclusive of tax).
Image from Happinet Online and Amazon Japan.
On the other hand, a clearer promo image for Keroro Gunsou Plamo Collection Musha Viper Robo [Eldest Son's Unit]
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Bigger gattai with more Viper Robo! ^^
June release, 840 Yen (inclusive of tax).
Image from Ruli PlaModel Forum.