[Request] Can anyone give me just an approximate? Asking for a friend

A friend is going to do a cosplay of this character (ABA from guilty gear), I really couldn't find a better pic of source material where this could be calculated.

Anyway, the height of the girl is 1.74cm.

Can anyone more or less try to tell me an approximate of what's the height of the key?

She needs the info to complete the cosplay, as a thank you, I can come back to the post and show you guys how it went.