Jim,
If you check the TinySA group WiKi, you will find TWO approved vendors on Amazon for the TinySA and Ultra or TinySA4.
They are SeeSii and AURSINC.
As far as the NanoVNA H and H4, R&L Electronics, in the US, is highly recommended as well as AURSINC on AMAZON.
I have purchased from all three vendors, and received original versions of TinySAs and NanoVNAs.
Clyde KC7BJE
Clyde Lambert