For embedded applications, there is official ECC support for all CPUs named Epyc or Ryzen Vxxxx or Ryzen Rxxxx.
There are computers in the Intel NUC form factor, with ECC support (e.g. with Ryzen V2718), e.g from ASRock Industrial.
All EPYC, including the embedded ones, do officially have ECC support
RAS covers more than just DRAM, but yes. Historically, the reporting interface is called MCA (Machine Check Architecture) / MCE. I think both AMD and Intel have extensions with other names, but MCA/MCE points you in the right direction.
Edit: as detaro mentioned in the reply, there is, and here's the source [0] -- that's what they mean by "RAS" on promotional pages [1]. That indeed looks like a nice option.
[0] https://www.amd.com/system/files/documents/updated-3000-fami...
[1] https://www.amd.com/en/products/embedded-epyc-3000-series