If you go to the website "Rimfire Central" there is a subgroup dedicated to Mossberg. There guys will know anything you need to know.
I bought one just like that marked Mossberg with a scope in .22 mag. In 1965 for $37 from Cinnabar Rifle Shop (Andy's) Petaluma CA. Traded it to my father for his Browning 1910 .380 to smuggle into VN in 1966.