You can use a Workmate if room is an issue, with the advantage that it can be folded up and put away when not in use.
I think you are better off making a loading bench then you are attempting to use a table or general purpose work bench. There are plans available on the NRA's website. This type of bench will prove to be much more rigid than a gerry-rigged table and should be a more convenient working height. Remember you need the front of the bench top to extend a couple of inches beyond the frame to give the press's linkage room to articulate. I inletted the front 8" of mine for a steel plate I then bolted to it. A hard surface you can pound on is always handy. I welded bolts to the steel plate in order to mount the press, and used a thin piece of plywood to act as a gasket between the two steel surfaces. One element of the bench you should not neglect is a shelf at eye level for your scale, concentricity gauge, or other measuring tools which work best when viewed at eye level.