Sipeed M1s Dock is widely available at last, just ordered one to evaluate it.
BL808 SoC : RV64 480MHz+RV32 320MHz+NPU BLAI 100GOPS, 64MB PSRAM, 2.4G WIFI/BLE
Native Linux support, all the sources (inluding bootloader and dts!) are available.

And this perfect tiny #riscv machine is available for ~$10

For another ~$15 you can get camera module and tiny display. Even JTAG adapter is available.
Also, there's NPU-accelerated face recognition model in "examples" section.

wiki.sipeed.com/hardware/en/ma