On Sat, 26 Sep 2015 11:30:50 -0700 (PDT), wrote:

Of course it has an obscure HP part number on it but I can see it
is a simple 7912 regulator.

It might be a good idea to check. Google for "HP part number cross
reference" and you'll find various lists. This one looks good:
http://www.sphere.bc.ca/download/hp_xref-free.pdf

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Jeff Liebermann
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