The swivel table itself is the valuable part. Mine came with adequate
but unimpressive centers and I had to make a base for it. The centers
could be turned from drill rod and the brackets made from cheap
machined angle plates like these:
http://www.use-enco.com/CGI/INSRIT?P...PMAKA=418-4515

If you can find one good ground angle plate you can use it to square up
the cheap ones.

Good luck
Jim Wilkins