I had been buying silicon power drives and they all failed prematurely (9 months at the longest). I switched to Samsungs and never had a single drive fail in years now.
Samsung’s consumer and enterprise SSD departments were (unsure if still true) basically separate entities that didn’t talk with each other, which was further confused and compounded by the OEM customized firmware nonsense which results in a lot of great hardware essentially having buggy firmware with no fixes.
I believe their very latest (non OEM) enterprise m.2 drives have streamlined the availability of updating the firmware, so the problem is seemingly less for those.
For the silicon power drives, if they just suddenly stopped showing up, then you may try doing a power cycle to see if that brings them back: https://dfarq.homeip.net/fix-dead-ssd/
I’ve had Intel and consumer Samsung drives I’ve brought back with power cycling. Older NVMe Drives seem especially prone to becoming unresponsive in older NVMe enclosures. Seems like less of an issue these days though.
I've only bought the pro level of the Samsung consumer drives (nvme m.2) and they've been stellar. I have no experience with their enterprise drives. I also wouldn't buy drives off of eBay. I don't think of eBay as cheaper than amazon/b&h/etc, and the risk of a fake is just so much higher on eBay.