The Middle East was quite an important market for BSA and they did special often what we would think of as gaudy finishes for that market. The Single barrel "Snipe" shotgun sold well there and were finished in colours rather than the traditional black. One order according to Knibbs book had Palm trees and animals in gold on top the barrel over the chamber.
Now the photos are not that clear on the gun but the fore stock reminds me of the BSA Single X11, the fore runner of the Snipe and a much better made gun, the Single X11 is a semi hammerless gun. Of course it may be of Italian or Spanish make as they also produced simple single barrel shotguns for this sort of market.
As for the "dishdash" I wonder how often the hem catches on the undergrowth? I have often wonder how they got on years ago when hunting cloaks were normal dress in colder climes?
-------------------- Don't let the bastards grind you down!