I think the only "unbreakable" records are Wilt's single season ones. His 48.5 mpg (he missed like 50 minutes all season), his 50.4 ppg, and his 27.2 rpg.
I think those are the only 3 records that have no shot at being broken.
The career one the least likely to fall is Wilt's total rebounds though. He is more than 6,000 more than Moses Malone and like 6,500 more than Kareem for some context (they are 3rd and 4th, Bill is 2nd a good 2300 or so behind Wilt). I mean Lebron has the 2nd most among active players and he was never an uber rebounder. Drummond would in theory be young enough to get close (just 28 years old and already 9500 rebounds), but there is no way Drummond is going to be able to play long enough and with enough minutes to get there. That said, there could be someone like Jokic that comes along that cleans up the glass and shoots well enough to stay in the league a long time that might eventually look like a real threat to Wilt. They'd have to play Lebron type games and have a much higher rebounding peak than Lebron. I think it is possible, though incredibly unlikely.
Stockton's assist record is also likely never to be challenged, though I could see that falling before Wilt's rebounding. For some context, Stockton has like 3800 more than Kidd who is #2. Which is insane, yet 15806 doesn't feel so far out there that someone couldn't get there.