Well if you can handle using a VFD or just swapping a 3 phase for a single phase motor then there are a few good looking machines on craigslist. I purchased a 240V (only) TEFC 1 hp single phase off ebay for $80 including shipping for a drill press rebuild and it worked out fine.
This is a month old but there's a clausing 22V for $600 out in Shrewsbury.
http://worcester.craigslist.org/tls/3532076040.html
IMHO, more press than any of the new stuff listed.
Another clausing down in Rhode Island but it's only a 15" model 1660 bench style and no pic....only $250.
http://providence.craigslist.org/tls/3547190928.html
Nice old Delta 17" (about a 5 inch quill travel) for only $100 also in Rhode Island
http://providence.craigslist.org/tls/3582997830.html
And a very serious looking 3 phase Powermatic 1200 over in Millbury for $800.
http://boston.craigslist.org/bmw/tls/3555133750.html
I think if you figure on spending another $200 for a single phase motor and swapping out then there are machines worth buying...or you can play in the VFD variable speed route. (teco FM50 from factorymation perhaps?).
The one that got away? A $200 clausing with a 3 phase motor......never ever look on craigslist if you can't buy
EDIT: You could always look over at plaza machinery in Vermont for a used drill press or parts for a drill press. And if you want to convert a bench model to a floor model that's also possible....and lally columns come in 3.5" and 4" diameter.