I got my first can of surplus H4831 about 30 years ago when I first started loading; the old-timer that I bought my Herters press from gave me a big 20lb tin of it (old oil tin or something as I recall).
That lasted me many, many years, and along the way someone gave me a few more 1lb cans that were marked "THIS IS WORLD WAR II SURPLUS POWDER. STORAGE LIFE IS NOT GUARANTEED." Price tag- $1.95
Then after that I ran across another dozen pounds or so from an estate, in old coffee cans, for really cheap. I used it in mostly 30-06 (not ideal), as well as everything from .243 to .300 mag. It always worked great, with the exception of another partial coffee can someone else gave me that was deteriorating (threw it out). I also passed along a fair amount of it for cheap to friends starting out.
Yesterday I finally used the last grain of the last pound. I know there are better powders for my purposes, and I sure appreciate ball powder over 4831 as far as metering, but it does feel a little like the end of an era for me.