They just aren't that expensive at the parts store............................
20 bucks or so, and I'm not saying this one is "special," just the first couple of Google hits, but it sounds about as I remember price.
http://www.oreillyauto.com/site/c/d....oap?ck=Search_N1745_-1_-1&pt=N1745&ppt=C0103
Equus 3620 Vacuum Gauge : Amazon.com : Automotive