theres no such item in the database, and i doubt k2 knows how to make new items with properties such as unrebirthing an item. they'd have to make it so that you can only unrebirth +1 rebirth, +5 rebirth, +11 rebirth, and +20 rebirth (dont know what +10 is in rebirth)

if such an item DID exist in the database, then im sure it would already be in the shops