I am looking at a rolling block for sale. I know nothing about value or exactly what this one is. It says Remington Arms. Last patten date 1876. Supposedly used in the Black Hills conflict by the sellers great great grandfather. He was a Calvary soldier. Not sure why anyone would scratch 1864 on the stock. Any info on value and exaclty what I am looking at would be greatly appreciated. He says its a 30 cal 08???