Thanks for the info guys.
When Dad acquired the rifle from the Legion basement, the stock was pretty much in pieces and had to be replaced, but as far as I know, the 257Rob barrel that's on it now is the same one that was on it then. So that's a big mystery...how & when it became a 257Rob.
I'd still like to know what the arabic script says.
Sure wish I'd have asked more historical questions about it when Dad was still around!