Re: C-Clamp or Pedestal
I don't see how it would be too hard to make your own base. Get a piece of iron about 3x5" or maybe a bit larger, nice and heavy, drill a hole in it that will accomodate your vise shank, weld a short collar slightly wider than the shank to the top of the piece of metal, then thread a eyed screw or something similar through the collar for holding the vise shank in place. Then coat it on the underside with rubber et voila. I like my pedestral, even though the XRay machine at the airport usually does not. Solid chunks of metal tend to draw questions. Pull it out of the bag and put it in one of the bins if you carry it on.
Working out a way to convince my university to allow me to hold my TA office hours on the nearby creek...