For those of you who have been corresponding about this, here is the latest.
I'm going to put together the first gauges this week. The catalog is a little
fuzzy on the point of measuring vacuum, so assume that it will only read
positive pressure. I'm going to go with a gauge model that reads 0-60 psi,
for the sake of accuracy in the fuel pressure range, but it could also read
tire pressure well. At least one of you wanted one that reads up to 100 psi,
and I can accommodate this request.
$20.00 buys the gauges and covers shipping. So if you want one, send your
check and mailing address to:

Brian Doss
563 4th St.
Butler, PA  16001

Thanks for all the helpful feedback!