I found a hobby sized (3 inch/7cm) vise that can clamp to a 2 inch or less surface for 22.50CAD (~16 Euro) locally once I started searching for the right word; perfect, decent heft, small enough to stow in the tool box... and best of all I didn't have to pay shipping on dead weight, in fact I got 25% off instead. To think I was making due with a 3 inch C clamp when I could have had
this - thanks for getting me looking again Taifix, I had given up on finding a decent vise when I got that C clamp.
I really miss having a shop or at least a benched corner of a garage for these sorts of things.