Personally, I would try the 2* cr2032 lithium coin cells and see how it
works.  It's not like you'd be the only one "violating" specs on these,
and it's not even clear that you're doing that.  You're just operating
outside the region that is well-documented.  If you need 50 hours and
tests show you getting 52 hours, I'd worry.  But if you end up getting
60 hours or more I'd think you'd be pretty safe.

The cr2032 battery is another size that varies quite wildly in price.
"cheap imports" regularly sell for about $0.30 on ebay, rather than the
$2 each you pay at radio shack.

BillW

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