If you can do the work it won't cost you much. Left thumb shifter, cable stop, cable, derailleur, bottom bracket (maybe) and a set of cranks. The Shimano FC-M311 are a good option for cranks. No new chain needed, the M311 comes with a 42 main ring. You could get the lot off Amazon for under 100 bucks. Whack on a set of Trekking bars and you're away. The District 8 already has front and rear rack eyelets.
For heavily loaded touring you might want to go for a 34T rear. The Acera derailleur will cope with that easily.
And before you ditch the brakes, have you tried a better compound pad and better cable?