It's the parable of the blind men and the elephant. Everyone's version of 1E was likely unique, because each group remembered where to find certain rules and chose to reject/incorporate stuff like weapon speed and other fiddly combat variables.
Even with OSRIC, I can't imagine playing straight 1E now, since I don't want to use a lot of those fiddlier rules (which I think were probably intended as optional rules, but just not labeled as such, given how systems like that were discussed in The Strategic Review/The Dragon magazine).
I think I mentioned it in this thread, but just in case here goes again.
It's also worth remembering the release schedule of D&D at the time. You had OD&D in 1974, Holmes Basic in 1977, AD&D Monster Manual in 1977, AD&D Player's Handbook in 1978, and AD&D Dungeon Master's Guide in 1979. B/X came out in 1981. Mentzer BECMI started in 1983.
There were no to-hit charts or rules in the PHB. So until the DMG was released a year later, people had to either make it up or look to Holmes Basic or OD&D to figure out how attacking worked. Groups started at different times with different levels of "completed" AD&D rules, looked to different sources to fill the gaps, homebrewed different solutions, etc.
A lot of people did not take the Basic line as a separate game line, as intended by TSR. They used it as the basic rules of the game. It was all D&D to a lot of people. So in practice you had people playing with AD&D classes and spells, but a lot of B/X and/or BECMI rules for everything else.
It was a real Wild West time for D&D.
Hard to beat the Gygaxian vibes, though.
I think the one that comes closest in modern times is Joseph Goodman, Goodman Games, and DCC RPG. Not the same, obviously, but to me at least, that stuff comes the closest.