From what I've read, each "bill" has four ounces of 0.999 fine silver in it. If that's truly the case, you have 48 ounces of silver which, at today's spot prices, yields $1,200+ as a starting point.
Being a complete set with the original case and paperwork, a collector with a strong interest in the set would likely be willing to pay a 10-20% premium over spot. It might be difficult to find such a collector, but I know from personal experience that they are out there! (No, I don't own one of these sets!)
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