I was at the Gooding auction in Scottsdale this weekend, and just as a data point a silver 1957 1900 CSS three window sold for over $160,000 USD. It was an extremely nice example and the bidding was pretty spirited.
The following prices are in US Dollars and include the buyer's premium of 10% and are rounded to the nearest dollar. Unsold lots are not shown. Gooding
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