Masked Swallowtail Angelfish
 

I am looking for a masked swallowtail angelfish to purchase, does anyone know where I can get one

ask your lfs to order you one?

You are probably going to have to watch various sites and also submit a request to be notified when available. I don't recall seeing any of those while looking for millesteeds but it probably couldn't hurt doing a basic search and see what turns up.

New York aquatics has a female on their website