MTN Electronics: LEDs - Batteries - Lights - Chargers - Hosts - Drivers - Components - 1-Stop-US Source

BlueSwordM has a group buy going on here that, in addition to his springs, includes SST-20:

He’s ordered some, and I lost track of what he is still planning to order, but you can always ask.

The other option is Kaidomain currently offers the SST-20 in multiple color temperatures and decent output bins.