Originally Posted by Iride01

If the new post slides up and down and the clamp holds it securely then what's the issue? It's a old bike. Is it just that the tube with the clamp appears twisted? Then that defect can become part of the character and charm of the bike. If anyone notices it can be a conversation starter. Possibly for a new friendship.

Like anything else, the area should be watched now and then for cracks. But to me, more damage will be done trying to twist it back into shape. Even if that's just more work hardening of the metal that causes it to crack later on in life. But sooner than if it'd been left alone.