I calculate 18 oz total. There are 8 rolls @ 40 coins per roll @ .05626 oz per coin. In any case, I think you would be foolish to refine them. As coins, they have a known identity. Everyone knows their value. When you refine them, you produce an unknown.
Also, you'll most probably never get the silver pure enough to sell as pure, unless you have a silver cell. This is true no matter what type material you're refining, but the manganese in them causes additional problems. The Mn will foul the cell and, therefore, you'll have to dissolve in nitric, cement the silver, and melt before using the cell. And, with this tiny amount, you can't afford to set up a silver cell.
How much are you paying for these? How much can you sell them for, as is? Even if you take a beating by reselling them, it will most probably be less than the beating you'll take by refining them.