Since you aren't a caster the bullets sources of oversize bullets are very limited, and a good fit to the bore is mandatory for good performance with such a large barrel. I highly reccomend that you get into casting, and order a bullet that fits your gun, but if you don't have the coins to invest or don't want to, try Mt Baldy Bullets. If they don't have a mold you can buy one that is right for your gun and they will custom cast and size, using LBT lubricant, for you, and do it very affordably.
If you would like to buy high quality commercial hand cast LBT bullets (and others) lubed with LBT lubricant, contact Mt Baldy Bullet Company, 1-307-754-5255.
Your oversize barrel will shoot jacketed quite nicely, as they are strong enough to ride the rifling, and though accuracy will be a little inferior to a smaller barrel, velocity will be higher than if the bullets fit properly, due to lower friction.
