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The link to Amazon is
https://www.amazon.com/Lexar-Professional-633x-64GB-UHS-I/dp/B012PL6K8M/ref=...3&sr=8-4-spell
I bought mine on Friday, free prime delivery today on a Sunday. I tried to give 1 of the cards a quick test. In continuous shooting mode, taken at approximately 20 ft using my K-3, Pentax 18-45 at F4 set to capture 6160 x 4000 captured in Adobe Digital Negative .DNG format 18 files were captured in approximately 8 seconds, file sizes around 29.5 MB for a capture of 531 MB while the buffer was being loaded. Then for the next 25 seconds the capture rate was an additional 38 files for a rate of 1.52 frames per second and 950 MB (38 Mbs) more data being captured.
Note: Those times may have been slowed down by a weak battery. I tried to see if it would keep up at full HD mode, but the battery died after 20 seconds. I will try again tomorrow.
I ordered 10 and they all appear to be in original packaging and were made in Korea.