Comment by camel-cdr

The CH32V407/CH32V467 is a bit more expensive, was $2.4 per unit two month ago, but supports the embedded subset of the RISC-V vector extension.

So you basically get a full AVX-512/SVE level SIMD ISA, minus FP support and with 64-bit SIMD width. But you still have LMUL, which will be great here to maximize utilization.