Yeah, ear drool wouldn't be very desirable. In all seriousness, that looks pretty dead on, Steve.
As for the durability, is it possible that they used something other than aluminum back in the day? I know nothing about lathing metals, so that's very possibly a dumb question. In any case, it seems like the rings would need to be thin enough to be fairly fragile unless the metal extremely hard.
It may be that they've just been treated with kid gloves over the years, but you'd think that they would have needed to be fairly durable as often as they were used on set. Maybe they just had extras made up in case they were damaged?