1918 Dated M23 Finn Luger

From what I can see, your pistol is made up of a 1918 DWM receiver, Mauser Banner toggle train, replacement barrel, replacement locking bolt (take down lever) and so-called "Black Widow" grips. The frame may have the Mauser "bump" but I can't see it clearly enough to be certain. The lack of a letter suffix under the frame serial number indicates that it's not an original M-23 frame. I'm not familiar with the crown stamp on the underside of the barrel but it's not the original DWM barrel which would have been in 9mm as the receiver was from a military issue pistol. If the front sight has parallel sides, it's a Finn sight. If the sides of the front sight slope then it's likely a Mauser rifle sight adapted for use on the pistol.

Your pistol is an excellent example of how the Finns made use of available parts to make working pistols. A nice addition to any Finn Luger collection.