I teach veneering at Woodcraft and wanted a pump I could transport easily, so what I did was buy a cheap "dolly" at the borg and build the pump system on the dolly. This will allow me to roll the pump into the classroom instead of carrying it. I have another vacuum pump but I've built it into my shop and it's not portable any more.
I bought the pump on eBay (there's a bunch of Thomas pumps being offered right now) and the brass parts from Joe Woodworker. The advantage of this design is that the pump doesn't run all the time - it only runs when the vacuum falls - so it's quieter in the classroom (only occasional noise).
I do have it wired so I can run it continuously - see pix 3. But that's for "just in case" I ever want to run it continuously. It was easy to wire it with the option so I did it while wiring everything else. Don't know if I'll ever use it.
Mike