BeagleV-Ahead RISC-V computer from BeagleBoard.org available now under $150

Says supported by Yocto.

$180 at Digi-key:

https://www.digikey.com/en/products/detail/beagleboard-by-seeed-studio/102991698/20380528

Certainly not a low-cost device, but may make a good Risc-V development machine.