mithril vest

[HerenIstarion]

Good logic, I daresay. It may well be so.

But compare:

(In Rohan, discussing royal burial mounds)

'Five hundred times have the red leaves fallen in Mirkwood in my home since then,' said Legolas, 'and but a little while does that seem to us.

It does not have a feel of someone twice less as old as period mentioned talking. But it does not eliminate probability of your reasoning, as there is no explicit reference to Legolas' actual age.