You should spend as much, or more on your scope as you do on your rifle. I have hunted with an inferior scope and missed getting a shot on a deer at dusk because the scope did not gather enough light and I could not see the deer through the scope. Any scope will do fine during the bright daylight, but on overcast days, or at dawn or dusk, you need a scope that will gather as much light as possible so you can see the deer through the scope. There are lots of great scopes out there. Just remember, you get what you pay for to a large degree with scopes. You can go overboard with some of the really higher priced scopes, but don’t skimp and get a “$59.95 special” scope either. I ended up purchasing a Leupold VX-III 3.5-10X40 for my Winchester .270. The VX-I or VX-II probably would have been fine, but I knew this would be the only scope I ever buy for my gun, so went ahead and spent a little extra to make sure I got a really good scope.
I found a good deal on a Leupold VX-II so I purchased it and mounted it on my Marlin 30-30. With the new Hornaday LEVERevolution ammo and the Leupold scope, I have started hunting more with my 30-30 again. I can get 100 yard groups with my 30-30 using the Hornaday LEVERevolution ammo almost as good as my .270.