I know there are companies that make synthetic stocks for marlins, try cabelas or any other catalog. A gun shop could probably order them too.

If you can't get a longer LOP by a stock alone, consider adding a recoil pad. It may have a double benefit.

Mine wears a peep sight, but my friend has a scope on his. Just a Bushnell Banner, dusk to dawn low power variable. No problems with it at all. I like the scout concept, never picked one up to check it out though.