Echo buttons are back in stock, and there is a promotion for $3 off if you buy two 2 packs (so four buttons total). Use promo codeBUTTON2PK.
These $10 buttons can be used to trigger an Amazon routine (not a smartthings routine), but they do have to be paired via Bluetooth to a nearby echo device.
Have that echo routine turn on a virtual switch in smartthings, then trigger a smartthings automation from that virtual switch coming on and you have good smartthings integration.
I’m glad to see these back in stock, they are one of my favorite button devices.