Oh, that's an interesting point about the Lee Loader. Hmmmm. Savage did make a 24 in .357/ 20 Gauge. The .357 out of a rifle length barrel is still a contender out to 100 yards, and lighter than .30-30 to boot. 20 gauge ammo is lighter too. As GJM recently pointed out, the Brennke 20 Gauge slug has a higher sectional density than the 12 Gauge. You'd give up some effectiveness from the buckshot though....
Also with a Lee Loader, you could use locally procured black powder too....
Edited to add: I also see that Lee makes a Lee Loader for .30-30. That and a bullet mold, and some primers might be a good thing to have.