Date stamps are another matter entirely, and I've not heard of one other than Trevor's (rather nice) cylinderback, which he has up for sale at present.
I don't have the info at hand just now, but the date was 1913, and about 5 yrs before the serial number would indicate from the list. (although absent other info, I'd favor the date stamp.) I just saw Trevor's mention of a date stamp and thought I'd ask him about the serial number as a possible test for the serial number list.
None of this means that the list is certainly correct but it suggests that evidence to the contrary has a high standard to meed in order to outweigh the bulk of affirmative information that has accumulated.
That kind of information evaporates over time, as the receipts tend to get separated from the instruments.
The old Fairbanks numbering system was applied to the mandolins that Vega made after 1904.
Prior to that, there's no evidence I'm aware of that Vega had any numbering system for their mandolins.
I sincerely apologize for any mistakes in detail or in form.] The date on the inside of the mandolin, on the neck block, as quoted from the TAMCO web-site: "It is dated on the neck block Nov 4 1913." He didn't mention it as a "pet. I can only say that this was surprising to me, very interesting, and the result of my reading from the TAMCO site of a cylinderback offered for sale bearing an internal date stamp (of which I had not previously heard).
This info is absolutely WITHOUT FINANCIAL INTEREST to me, and is included as a service to those who are interested in Vega instrument serialization information.