Not familiar with these counter stamps at all, anyone here have one? They all were done on Ike Dollar coins, a bit too big for my collection. Anyone? http://www.tokenandmedal.org/Journal/Journal_files/Counterstamped_Coins_of_Mel_Wacks.pdf https://www.ebay.com/itm/1979-Year-...853793?hash=item54961ecce1:g:OfMAAOSwz19gLGsF
Mel Wacks has made counterstamps on many coins since 1976. His items show up and can command fairly large premiums. I don't have any but have seen some of these before in eBay auctions and on various forum threads. https://coinsweekly.com/whoswho/wacks-mel/
Actually I have seen some done on Peace dollars, particularly the commemoration of the Camp David Peace accords betwixt Israel and Egypt.
If you look through that first link in your post, there are pictures of a Franklin, Peace Dollar, Mexico Peso, Kennedy Half, Austria Maria Theresa Thaler, and some more coins with various counterstamps done by Mel Wacks.