Hello mechanic:
Just a guess, maybe a type 38 arisaka, the ladder looks the same but I don't know about the screw. I went out to the smokehouse to look but the bug spray was too strong to take the stock off for confirmation, Tonight was the semi annual bug-spraying night.lol, If you are still curious later and no concrete answers I will be glad to look. Thats about all I do is tinker anyway since I retired.
safety first
HM