The weapon was in regular cash shop a year back. Bought it then.. It has been switched to Donor a few months ago.
Unless I'm missing something the donor equivalent Sparking Bluebird looks different and can be equipped over all weapons. Edit: Fly Blue Bird looks the same, actually. But still equips over all weapons.
Yes it is the equivalent of ''Fly Blue bird'' it's the exact same item except you can't equip it on gun and knuckle
