If the import marking says Turkey etc.. it undoubtedly is a Turkish used Gew.98, and I wouldn't put $375 anywhere near the rifle. The rifles were military aid during the war, Germany spent enormous amounts of money keeping them in the war, especially on their railroads, and these rifles, in part, were sent during the war. They probably bought more Gew.98's on the surplus market after the war, as Turkey had a lot of problems in the interwar period, but I do not follow Turkish topics too closely.
Generally Turkish used rifles were rode hard, often very hard and usually the stocks are crispy or at best well done. The metal is usually refinished (any rifle that is refinished by another country, besides Germany, is shooter or junk in my book) poorly, often weak markings due to the refinish process or wear-use, and I just do not think they are worth buying except for parts. Sometimes they have armorer parts, sometimes a good cleaning rod ($50 there), or a part or two is worth keeping, but overall they are not worth much to me, when you consider you can buy a nice bolt mismatch for $350-500 that is straight up Imperial.
Anyway, I doubt you would lose much at $375, but there is no upside at that price down the road, most collectors I know have zippo interest in them, and those that do, generally, are not "collectors" and have a shallow interest level in German military rifle collecting (they move on quickly)
