I have ended up with another stocked action, this time without barrel, forend, AND sideplates. I’m thinking it’s an Excelsior live pigeon gun, but I do not know German guns. Anyone able to help identify?

Any possible resource for the parts needed to complete the gun?

Thank you.

Pictures: https://drive.google.com/drive/folders/1-pPrIpRSIgAVrS-rCK5pQxvXtokXhtTL