For quite a while now Beryllium copper and nickel have required numerous safety measures whether in manufacturing or to work with these metals . The reason is because it is highly carcinogenic to either breathe the fumes, midst or metal dust whether in manufacturing or if you sand the metal in repair. This is why Ping and others will not work on these products. However, Beryllium alloys, copper and nickel are still being used in other applications. Beryllium is classified as a strategic and critical material by the U.S. Department of Defense. I have seen posted at times it is banned. Not so, in 2014 the USA produced 270 metric tons and imported another 68 metric tons of beryllium. That was a 15%+ increase over 2013 and the increase continues. The golfers who continue to use the wedges or irons generally are either unwilling to sell them or the selling price is on the high end if in very good to excellent condition.
If you have ever played these clubs, you are either a fan or not. They have a small cult following. I did not like the irons (Beryllium copper) which I tried years ago, but when I tried a Beryllium nickel Ping putter years ago, a friend owned it and would not sell, I keep my eye out for a model I wanted. It was on FGI that I found two for sale. One was the model I sought. I bought them both.
If you see them on ebay, be cautious in buying. Check to be sure the metal identification is correct.