Its a typical 125 year old Purdey.Almost certainly made as a non ejecter and later converted, seen numerous guns like this with different ejector types fitted. The stock is worn hence lack of points ,the lock pins are loose so not lined up . Its an old gun that has seen better days ,may even have been rebarreld certainly looks like they have been re-engraved, but hard to tell from the picture.If you have any doubt then get it to some one who knows what they are talking about.