There are now over a hundred RISC-V CPU cores listed on riscv.org‘s RISC-V Exchange! Amazing. If you need a RISC-V CPU core, you’ll likely be able to find one that suits your needs… if you evaluate a hundred CPU cores to find it.
Or, now, you can configure exactly the core you need, and have it built in seconds, for free! WARP-V is the most flexible RISC-V CPU core available, and recently, Indiana University student, Adam Ratzman, created an online configurator for WARP-V. If you need a low-to-mid-range CPU core, check out Adam’s work at warp-v.org.