I just paid $10 for a used one. Reg.No.F. 7432C
About $30
5-100 usd
See link below-
20-50 usd
You can't it is not designed to come apart. Time for a new Scope.
No
Send it back.
The typical Marlin 39A does not have a scope. They are drilled and tapped that one can be added.
Priceless! ... actually around $450 depending on condition, but they were made by Tikka of Finland some as early as the 60's, they are quality firearms for the price
It's worth between $10 to $15 used.
Just bout one at auction with 4x32 tasco scope for $110
There's several models. If it's a 4x32, then about $25. If it's a 3x9x32, then about $30-40. If it's 3x9x40, then about $40-60. I'm not sure if there are other configurations, but you get the general idea.