The automotive manufacturers, saw this comming in the mid 80's and all of them switched to hydraulic roller cams and the only changes were the oil additaves, due the federal regulation for catalic converters. Now almost all cam cores are chinese made and the lifters are probably also. I know some cam manufacturer are now offering nitrated cams, they all used to be nitrated. I haven't checked the hardness of a set of lifters, but have thought of reheat treating a set and see what material they are made from. I know i could flash crome a cam and reharded the lifters and they would live with 135lbs of spring pressure which is necessary to run a good flat tappet cam at 7,000 rpm's. But i know for a fact the spring pressure in my El Camino with trick flow heads is only 100/110 lbs. The cam should have never gone flat. If i wasn't so dam old i would get after this problem and figure it out since i have all the resourses to do the heat treating anf the nitriding. Right now all i can do is hope the new cam doesn't go flat/die before i do.
Zip.