I bought a brand new San Jose frame on eBay and had it modded for gears a couple months ago by Yellow Jersey in Madison, WI. They charged me like $115.00 to braze on a derailleur hanger and two threaded head tube cable guides and a driveside chainstay guide, tap the BB shell for a plastic guide (they included the guide and the screw) AND return shipping, IIRC. The work was fine and quick- about a week from when they got it I had it back. Total set me back about $150 with initial shipping, packing stuff, etc. Of course, the dealbreaker for many would be that the brazing means a refinish (in progress) but the frame's not expensive or valuable enough to be shamed by rattlecan paint. I didn't like the original color (red, white panels) anyhow.
Anyhow, I love the frame. Not spendy tubing but it's light enough to suit my needs.
No digital camera to show you pics, but I wanted to point it out because YJ does it for a LOT less than pretty much everyone else I talked to about it (they told me that they do a lot of this stuff every day so they're set up for it and it costs less) and it might be within your price range. Also, it allows you to use both derailleurs without all that cable housing and zipties. It solves any spacing concerns you may have.
I don't know what your frame's spacing is, but mine is 132.5 at the front of the track ends (closest to the seatpost).
I don't know if that was Bianchi's intent or not.
If not, yours is probably either 130 or 135.
Last edited by B17; 05-13-10 at 10:29 PM.