Trusted expert on Regular Issue Proof Sets. Buy Proof Set online 24/7 with Golden Eagle Coins. Call Trusted coin dealer since Own the highest quality U.S. coins of with this official U.S. Proof Set – with all 5 coins bearing the San Francisco "S" mint mark, and 3 special silver issues! Mirror-Like Cameo Coins USA Coin Book Estimated Value of S Proof Set is Worth $ or more. Click here to Learn How to use Coin Price Charts. When buying or selling your United States, proof sets make sure all original U. These are approximate retail prices and wholesale values. Over time the average coin values based upon current market conditions have fluctuated very little. The actual offer you receive from a particular coin dealer will vary depending on the condition of the 1994 proof set coins and some other factors that determine its worth. Mint offices in Philadelphia.