Ejectors were introduced in 1888. By 1892, Diamond quality ejector guns were designated "250" grade. If you are willing to share the serial number it would help Ken's research as official keeper of the Daly data base.
You have a Lindner built gun and to me more desirable than post lindner Prussian Dalys. The terms "Empire" and "Superior' don't show up until several years after lindner died.
Dalys were stupid expensive in the day and many surviving examples have been rebarreled. I currently have two rebarreled
Diamond Quality Dalys that are great shooters. It's expensive but very few 20 gauge Diamond Quality Lindner Dalys were built and fewer survive today. Bring it to the Southern.