I found these at a church sale, you might be able to find them at a thrift store, a garage sale, or a sports resale shop similar to play it again sports.
The clubs in question are the Ping Eye 2 Beryllium Copper Irons. The steel version is not as valuable, but still worth buying if you can get it for $20 or so. I sold mine for $500+shipping but I probably underpriced it. There is a set for sale for about $4k right now on a privately listed site right now. I don’t remember the name but it shows up if you google “BeCu Ping Eye 2 Irons for sale”. I would recommend playing with these clubs if you can, they feel exceptionally good.
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