I've Googled the legible part of the makers name and got the following hit. Click on the URL
(You need to Login or Register to view media files and links) and go to item 347 where a 'Beau Fusil De Chasse' is pictured and described in French. There are some pictures but I don't know how much you will be able to gleen from them. The name and occupation engraved on this weapon is the same as yours. No initial is given.
Not much I'm afraid, but every little helps I suppose. OOps nearly forgot. This is a shotgun, carved stock and engraved and inlayed. A museum piece.
On a second site
(You need to Login or Register to view media files and links) also item 347 is a similar, if not the same description of the weapon which ends:-
Allemagne, vers 1880. Ce fusil est une commande royale
durant le règne du Roi Louis II. 5è catégorie. N°6044 Which if my less than schoolboy French is any use reads Germany circa 1880 made under Royal command during the reign of Louis II.
It looks like you have your hands on something a little out of the ordinary. Must be worth a couple of bucks anyway.
Seriously though, a quality weapon needs expert attention by a professional restorer. Not a quick sanding down or a re-blue. As much as possible of the original weapon and finish should be retained. For value you will also need specialist advice.
Harry
Edit. Ludwig (Louis) II, King of Bavaria, Ludwig Friedrich Wilhelm; sometimes known in English as "Mad King Ludwig" and as the "Märchenkönig" (Fairy-tale King) in German. (August 25, 1845 – June 13, 1886) was king of Bavaria from 1864 until his death.
I think the value of your rifle has just gone up, Deiter had the equivelent of a By Royal Appointment Gunsmith to H.M Louis II.
Harry