A 45-70 is a breechloading cartridge gun. This is not a 45-70. 45-70 originally stood for a .45 caliber bullet (barrel bored and rifled for .45) in a brass case that held 70 grains of blackpowder. This is a muzzleloader hence the need for a ramrod and a percussion cap. If the staples caused the crack I would assume they added the bands to strengthen their original staple repair.
"The Model 1842 Percussion Musket was produced in both Armories from 1844 until 1855, and was a .69 caliber smoothbore with a 42 inch barrel. Springfield produced 172,000, and Harper's Ferry manufactured 103,000. This weapon was the first Armory produced Musket with completely interchangeable parts, and was the last smoothbore arm made in .69 caliber. About 14,000 of these muskets were rifled by the armories between 1856 and 1859.
The shape of an American Musket was fairly standard from 1816 until 1842, having a full walnut stock, a long barrel of 42 inches, and three barrel bands. The rifles were generally shorter and of smaller caliber. The adoption of an American Rifle-Musket was a compromise in caliber, with the large, "three-band" design persisting in the Model 1855 Percussion Rifle-Musket."
If your barrel is a smoothbore, you have a musket. If it is rifled, you have a rifle. Your date appears to be 1843. A goood loupe will show you if that last number is a 3 or an 8 but the internet pics look like it is a 3.