In article ,
aemeijers wrote:

I always hating using fresh drill bit sets. When you wear out/lose/break
one, finding a same-size replacement is always a pain. But like Sears
tools, sets are the only logical way to buy them- one-by-one is insanely
expensive.

Go to an industrial tool store and buy the good ones by the dozen. That
way when the one in the index goes south, you've always got spares on
hand.