If your gun is in good shape Privi 139 gr loads should be fine to build up a quantity of good quality brass for reloading.  Start with opening loads in new/ modern loadbooks like Lyman and Hornady and work up until you get a good load.  Don't go too hot but I would not worry about shooting Privi loads out of your Krag part of the time at least.  139 gr to 160 gr bullets should work the best.