Intake vacuum gauges aren't as common as they used to be. But you can still get them. Problem is trying to find one as a set of OTHER gauges. I couldn't really find something like that. But it's easy to get the oil pressure and voltmeter gauges, even in a dual set.
I did find THIS ONE at Amazon, which is mechanical (no juice required) and is of fairly high quality and comes with everything for the install. Also costs about 75 bucks. Just saying. There is a cheaper version for about fifty bucks but I don't trust it.
The one I linked takes an incandescent bulb, so it isn't TOTALLY electric-free as they say. I would suggest switching out whatever bulb they include with the gauge to an LED equivelent. If you want to get really crazy, you could go with a color LED.