[ithacaartist]

I've only seen one Persian in person, and I don't remember if its barrel had the stamp to which you refer. My general recollection is that the placement of markings adhered to military style, and I'm pretty sure the barrel should be numbered as you suggest, albeit all in Farsi. I would say that the "59" sear bar would make it not all-matching. Hmmm... what would a Persian Artillery "shooter" be worth? Seriously, though, you have an issue with the auction house--their description and this anomalous Western numeral.

Here's a pic of that gun, showing the left side, including the sear bar. The operative digits for serial number marking look like a dot, then a "9" shape. Sorry about the gun show pic quality, which does not show the marks on the sear bar clearly. But it does show that they are not the usual "Western" Arabic numerals.