That sight that you should be getting tomorrow probably won't mate to that dovetail without drilling and tapping it from the looks of it. Are there at least two threaded holes on the top? If so, the TacSol rail sight is about $40. Allows you to skip dovetail issue, saving time and effort.

The crown ding may or may not affect accuracy. I'd get sights on it and test fire before scrapping the barrel.