Hi all; I have a pair of 8" Kurt-style vises that I need to raise vertically around 3 or 4". This is a really silly question, but what's an in-expensive way to do that? I've not really found anything cheaper than about $50 an inch of height - 12 x 12" plate steel in that case. Accuracy is not much of a problem in this case so it doesn't need to be a super flat material. It needs to be something that can handle coolant and be there for a reasonably long time. Any suggestions? I was shocked to find that it would be so expensive to lift the vises. Thanks in advance!

-Mike