[Utilizer]

They'll be on microfiche records somewhere, and probably on computer records, somewhere. If not, then I guess that makes you "illegal" .

*laugh* That is truly funny. Microfiche did not exist when the county records were destroyed. I know: I researched for years. Just as a quick note: I am of mixed ancestry, and the various clans I am related to would laugh themselves silly at the thought of I being "illegal", plus at least a decade of service (not to mention the threat of Involuntary Recall) in the Military should give pause to most that might have any reservations about any loyalties. *grin*

[Yosemitest]

Some organization has a copy of that birth record, that you've been a member of, at one time or another.
Either in a driver's License record, back on your very first driver's license, or if you've ever a member of the military, or State National Guard or Reserve.
Someone will have a computer copy of it, and I'd bet ever your first tax filing might give you a hint of where to look.
If you've ever been in a hospital, try that hospital, or the insurance company that paid that hospital bill.

[Yosemitest]

Source:

"... Microfilm first saw military use during the Franco-Prussian War of 1870–71.

... Libraries began using microfilm in the mid-20th century as a preservation strategy for deteriorating newspaper collections.
Books and newspapers that were deemed in danger of decay could be preserved on film and thus access and use could be increased.
Microfilming was also a space-saving measure.
In his 1945 book, “The Scholar and the Future of the Research Library,” Fremont Rider calculated that research libraries were doubling in space every sixteen years.
His suggested solution was microfilming, specifically with his invention, the microcard.
Once items were put onto film, they could be removed from circulation and additional shelf space would be made available for rapidly expanding collections.
The microcard was superseded by microfiche.
By the 1960s, microfilming had become standard policy.

... "

[Yosemitest]

"Just as a quick note: I am of ... at least a decade of service (not to mention the threat of Involuntary Recall) in the Military ... "

If I were you, I'd start my research for a copy of the lost birth document here,
and I start at the nearest Consolidated Base Personnel Office (CBPO), at their Customer Service area.
Explain to them, your problem and ask them where to start to find or get a copy of your "lost" document.