Hi James809. This is my favorite NVMe 3.0 SSD; I personally purchased three over the years with my own money. Below is the 2TB and 1TB variants.
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SAMSUNG 970 EVO Plus SSD 2TB
$215.15 USD
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SAMSUNG 970 EVO Plus SSD 1TB
$112.73
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Also, you might need a tiny screwdriver sized for a M.2 screw, in case you don't already have one. Some of the brand new Asus boards come with tool-less M.2 slots, but most currently do not, so you might need one of these:
https://www.amazon.com/s?k=m.2+kit
FYI: The screws should already be present with the board.