I bought a Stagg EDB 3/4 just to dabble with upright playing. It came converted lefty from Adirondack Guitar for about $450. I gotta tell ya, for $450, it's a pretty damn good instrument and loads of fun. It may not be the best EUB out there, but you can't beat it for the price. It can sound very close to a double bass with proper EQ, mic'ing, etc. (Do a thread search for "Stagg" and you'll see some previous discussions about it). There are links out there about how to further improve it via shielding, upgrading strings, etc. and I did most of them to further improve the instrument. Just putting a "real" set of acoustic strings on it made a huge improvement. I added a cheap transducer PUP under the bridge and I blend it with the onboard PUP through my Zoom A3 pedal before going into my Eden Navigator head.
http://www.youtube.com/watch?v=QsTlexheBu4