I'd say it's a grade 4 Flues. The pin placement can be no other than Flues; the strutting pheasant seems typical of a grade 4. Am I correct the butt stock has been replaced? The comb appears high and straight for a gun of this vintage. If you look at the pistol grip, the bottom line doesn't run from the front of the grip to the top of the heel. I can't imagine Ithaca making such an amatuer a mistake on a gun of this quality.