If you get a BP with the 3 phase table drives, then a rotary phase converter might be the best. While it is possible to run multiple motors on a VFD, it might be more trouble than it's worth. Many BPs have Servo brand table feed motors or similar, and thus they are 120V AC motors so no 3 phase needed for them.
I use Search Tempest https://www.searchtempest.com/ Allows you to search all of Craigslist, Ebay and Amazon in one shot. Just set the distance you are willing to travel and your price range and press search.I'm open to suggestions on places to look for these mills, I'm in ND, and there isn't much available in my area. Also any reasons to go Series I or II?
Series I or Series II, just depends on how large of machine you need. The Series II is a much larger machine. Also, don't discount the higher quality import machines, they are just as well built as a BP.