Get feed water into your boiler reliably with one of these choices:  Dual action twin piston pump running from your engine shaft, a good hand pump with lots of volume, or an easy to run  Penberthy steam injector.

At last, you have a source for quality pressure, and vacuum gages.  Standard four (4) inch pressure gages are 0 to 200 psi, exactly the choice range for most hobby steam applications.  Also available are vacuum gages in matching four (4) inch solid brass cases to match.  Priced reasonably plus postage.  No longer do your gages have to look as if you raided the junk shop.  Please inquire further for mounted two and three GAGE BOARDS.