One pc in my 1e campaign lived until 47th level. That's the highest I can recall.
That's not exactly accurate- let's say she didn't die her final death until then, and she might have just hit 48th level. She kept getting raised and getting lucky on the survival roll, and she hung out with a longterm high level badass party, then their heirs, then their heirs, etc.
My 1e campaign, which lasted for a long long time with various pcs and players, eventually had like 1 guy at about 20th level, several in the 12th-16th range, probably 6-10 or so in the 8th-11th range, and maybe fifty to seventy? pc between 1st and 7th. This was spread amongst many different groups, some with the same players, and throughout the game world. And of course it was an average- many of these guys died, some were raised, a handful became gods, etc. over time.