I decided I would bite on the Woodcraft deal myself and received mine about a week or so ago. But the base in their picture is a casting, and the one I got was a stamping. However, after using it for a week, the stamped base seems to be perfectly adequate, and I am really liking this vise. I too was using a Parrot vise before this, but the cheap jaw screw stripped on me about 3 weeks ago, so this is what led me to buy the PM vise. It is much, much more heavy-duty than the Parrot vise, and the fact that it comes with padded wooden jaws is a plus for me.
As far as backordered parts, that is an Acme thread on the mounting screw, so hard to improvise something to get it set up temporarily, but not impossible. I was fortunate mine came complete.
Matt