Jim at Etowah Valley Equipment will build you anything you want. I think he makes it all in-house, so a bare pump stand should be no issue.
Does it have to be brand new? I see used systems on ebay frequently. Usually they don't bring diddly squat. You could buy a whole system just for the stands if you want to build something up to your desires.
We build single and 2-bay stacked stands and bolt multiple stands together at the site. As a rule, stands built for a specific number of bays will cost quite a bit more.