Hey Mauser,
Buy up some of the Winchester factory ammo. and see how it shoots. Midway, Graf's, Natchez, etc. has it from time to time. I think the only load is the 180 grain. All these guys have brass from time to time also. Stock up. I don't think they will discontinue factory loads for the .30-40 anytime soon since there are a brazillion rifles out there for them. Winchester may stop but the custom guy's will still make it and a major player will step up and take over.
I have two. A Browning 1895 which is new and I have never shot. (This is mortal sin for me which must be corrected) and a Ruger #3. I bought the #3 at a gun show this year for $650 NIB. It shoots 3/4" groups at 100 yards with 200 gr. handloads. It shoots 1" with the factory stuff. I am going to make up some 150 gr. handloads for our tiny Texas deer. The .30-40 is a great caliber and I can say that it is not very finicky.
Have fun!
BT53