Absolute power corrupts absolutely.
The solution is to repeal the federal reserve act and all the actions done under color of law e.g., executive orders of FDR, and to reissue double eagles as US money.
As for the specific coins and their ownership, the feds have already compromised with a previous coin owner and in so doing, set a precedent. They should treat these coin owners the same way by negotiating a sale price in near worthless paper currency at gunpoint. Of course, not having possession of the coins will likely affect the market price in the estimation of looters.
Supreme Court appeal? Waste of effort. They are at least as corrupt as the rest of the federal government. Expecting a federal judge to rule against the feds is foolish.