Man! PE City. I have the 4" Hold 'n Fold & it's invaluable, you're mad not to have something like it. You can get these from IR Models (NSW coast):
http://www.irmodels.com/. Hold 'n Fold comes in different sizes which is handy, although you might need the big guy for your stash. I got a set which includes the Hold 'n Fold, a set of rollers (various sized dowel + an aluminium rack w. matching troughs) & a few bits of black acrylic. The latter are great for cutting etc & not losing bits, although you may as well get your own cut at the local supplier.
Please keep us posted w. progress pics, I'd love to see how the WEM stuff turns out.