If you dont mind using iron sights i would look into a 45-70 single shot. Those have long barrels. Another really great option is the old 30-40 Krag in its full length rifle form. This is a mild cartridge with easy recoil and report and its quite a decent performer. The only other options i can think of are old Mauser milsurps but they have risen in price and getting a good one is costly. One of the best was the 96 Swedish mauser and its long rifle length barrel. Also look at the 7x57 Chilean mauser, its just as good and they pop up at decent prices.
