Here is a list of all the upgrade kits for Kingdom Blaster and Eject:
Arm Fillers/Fillets (Upper Limb):
https://www.ebay.com/itm/154790485626
Forearm Covers:
https://www.ebay.com/itm/154819239305
Leg Fillers/Fillets:
https://www.ebay.com/itm/154790493696
Antenna/Gun set:
https://www.ebay.com/itm/154790506885
Speakers:
https://www.ebay.com/itm/154790506116
Gun for Eject:
https://www.ebay.com/itm/154822312390