The easiest way is of course is to try playing the disc on PS4. If it plays, its an original because you cannot play pirated/copied discs on PS4/Xbone. Now, if you want to check the disc without playing it on a PS4, you need to be a bit carefull.

Apr 01, 2018 Best Buy® Product Availability Best Buy may sometimes limit quantities purchased per person, per household or per order. These restrictions include orders placed from the same BestBuy.com account or credit card, and sometimes even orders that use the same billing and/or shipping address. Nintendo Switch Console in Stock Checker, Tracker and Locator

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PS4: Serial and Model Number Location - PlayStation

Best Buy may sometimes limit quantities purchased per person, per household or per order. These restrictions include orders placed from the same BestBuy.com account or credit card, and sometimes even orders that use the same billing and/or shipping address.

How to Check Whether a PSN ID Is Available - wikiHow Dec 31, 2011