What would you use 7 power for on a .30-30 except possibly load development?
Seems like the whole raison d'etre of a Marlin .30-30 is a dead nuts reliable workhorse for taking game from close in (where speed of mounting may be important) out to about 200, maybe 250 yards. A straight 4X scope would go with that concept like grape jelly goes with peanut butter. The longer eye relief isn't a factor in preventing scope eye but in getting inside the eye box when the rifle is mounted quickly.
If a peep sight isn't in the cards then a straight 4X is the next best thing.
Besides, a Leupold 4X is what my Marlin .30-30 wears, so I
am a bit prejudiced.