Nope, not all. The two I've seen with a brass 3/8-11 pin did not have the ivory dot. We've also encountered a few others with a 3/8-10, both stainless and brass, without the dot. They just had the tip of the pin filed or machined down and polished. I've heard the thing about the early vs the late ones, too, but one we had was the last cue out of their shop and I don't recall it even having the dot. McChesney and Wright use to sell most of their cues from what I understand...c. 1988-1990.
The majority of the ones you will see though have the stainless 3/8-10 pin with the small ivory dot on the tip like the ones featured on our site and Scot's photo gallery. "Majority" not meaning there's a lot of them....just percentage-wise. I doubt there is more than 150 or so Libras in existance. IMO they are one of the greatest made and hitting "unknown" cues of all time. I'll put the hit and feel of their cues up against anybody's.
Sean