Sorry if this question was asked before.

I am currently waiting for a "Phyrexia: All will be one" Set Booster. I ordered from a site which in any way seems to be legit, as they got actual customer support, etc. The Display was marked with "new ones are already ordered, delivery may take longer" which is okay as i can wait. My question is, is there a chance that the store also just tried to get new displays and does not know if they'll get one or are these cards still produced and its safe to say i'll get my Display? Otherwise i'm thinking about buying from Amazon for 30 bucks more, before it's sold out there too.

Is there a specific number of cards that are produced from one set or does it differ?

Thanks in advance for your answers!