Such coins must be authenticated before sell. I have a source through which you can have coins authenticated and sell them. See the chart below for prices. Click the black coin banner on this page to have coins certified and sell for retail prices. I do not suggest that you sell to coin dealers.
Coin dealers pay wholesale prices.
Start bidding at twice the value of the highest listed price listed for the type of coin you have. No data is available, I am trying very hard to find the time to finish this important page.